Nasal stimulation devices and methods

ABSTRACT

Described here are devices, systems, and methods for treating one or more conditions (such as dry eye) or improving ocular health by providing stimulation to nasal or sinus tissue. Generally, the devices may be handheld or implantable. In some variations, the handheld devices may have a stimulator body and a stimulator probe having one or more nasal insertion prongs. When the devices and systems are used to treat dry eye, nasal or sinus tissue may be stimulated to increase tear production, reduce the symptoms of dry eye, and/or improve ocular surface health.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/256,392, filed on Sep. 2, 2016, which is a continuation of U.S.patent application Ser. No. 14/313,937, filed on Jun. 24, 2014, issuedas U.S. Pat. No. 9,440,065, which is a continuation of U.S. patentapplication Ser. No. 14/256,915, filed on Apr. 18, 2014, issued as U.S.Pat. No. 8,996,137, which claims priority to U.S. Provisional PatentApplication No. 61/814,166, filed on Apr. 19, 2013, and titled “NASALSTIMULATION DEVICES AND METHODS,” and to U.S. Provisional PatentApplication No. 61/860,839, filed on Jul. 31, 2013, and titled “NASALSTIMULATION DEVICES AND METHODS,” each of which is incorporated byreference herein in its entirety.

BACKGROUND OF THE INVENTION

Dry Eye Disease (“DED”) is a condition that affects millions of peopleworldwide. More than 40 million people in North America have some formof dry eye, and many millions more suffer worldwide. DED results fromthe disruption of the natural tear film on the surface of the eye, andcan result in ocular discomfort, visual disturbance and a reduction invision-related quality of life. Activities of daily living such asdriving, computer use, housework and reading have also been shown to benegatively impacted by DED. Patients with severe cases of DED are atrisk for serious ocular health deficiencies such as corneal ulceration,and can experience a quality of life deficiency comparable to that ofmoderate-severe angina.

The etiology of DED is becoming increasingly well understood. DED isprogressive in nature, and fundamentally results from insufficient tearcoverage on the surface of the eye. This poor tear coverage preventshealthy gas exchange and nutrient transport for the ocular surface,promotes cellular desiccation and creates a poor refractive surface forvision. Poor tear coverage typically results from: 1) insufficientaqueous tear production from the lacrimal glands (e.g. secondary topost-menopausal hormonal deficiency, auto-immune disease, LASIK surgery,etc.), and/or 2) excessive evaporation of aqueous tear resulting fromdysfunction of the meibomian glands. Low tear volume causes ahyperosmolar environment that induces an inflamed state of the ocularsurface. This inflammatory response induces apoptosis of the surfacecells which in turn prevents proper distribution of the tear film on theocular surface so that any given tear volume is rendered less effective.This initiates a vicious cycle where more inflammation can ensue causingmore surface cell damage, etc. Additionally, the neural control loop,which controls reflex tear activation, is disrupted because the sensoryneurons in the surface of the eye are damaged. As a result, fewer tearsare secreted and a second vicious cycle develops that results in furtherprogression of the disease (fewer tears cause nerve cell loss, whichresults in fewer tears, etc.).

There is a wide spectrum of treatments for DED, however, none providessubstantial efficacy for treatment of the condition. Treatment optionsinclude: Artificial tear substitutes, ointments, gels, warm compresses,environmental modification, topical cyclosporine, omega-3 fatty acidsupplements, punctal plugs and moisture chamber goggles. Patients withsevere disease may further be treated with punctal cautery, systemiccholinergic agonists, systemic anti-inflammatory agents, mucolyticagents, autologous serum tears, PROSE scleral contact lenses andtarsorrhaphy. Despite these treatment options, DED continues to beconsidered one of the most poorly treated diseases in ophthalmology.Accordingly, it would be desirable to have a more effective treatmentfor dry eye.

BRIEF SUMMARY OF THE INVENTION

Described here are devices, systems, and methods for treating one ormore conditions (such as dry eye) by providing stimulation to nasal orsinus tissue. Generally, the devices and systems may be configured tostimulate nasal or sinus tissue. The devices may be handheld orimplantable. In some variations, the devices may comprise a stimulatorbody and a stimulator probe, where the stimulator probe comprises one ormore nasal insertion prongs. The stimulus delivered by the stimulatorsdescribed here may in some variations be electrical; in othervariations, it may be mechanical, thermal, chemical, light-based,magnetic, or the like. When the devices and systems are used to treatdry eye, the methods may comprise stimulating nasal or sinus tissue toincrease tear production, reduce the symptoms of dry eye, and/or improveocular health. The methods may further comprise treating dry eye byregular activation of the nasolacrimal reflex.

In some variations, the devices described here comprise devices forstimulating nasal tissue of a subject. In some variations, the devicecomprises a stimulator body and a stimulator probe connected to thestimulator body, wherein the stimulator probe comprises a nasalinsertion prong, and wherein the stimulator body comprises a controlsubsystem to control a stimulus to be delivered to the subject via thestimulator probe. In some of these variations, the stimulator probecomprises at least two nasal insertion prongs. In some of thesevariations, the at least two nasal insertion prongs are self-aligningwhen inserted into the nostrils of the subject. In some of thesevariations, the stimulator probe comprises at least one electrode. Insome of these variations, the stimulus is electrical. In some of thesevariations, the electrode comprises a hydrogel. In others of thesevariations, the electrode comprises one or more of platinum,platinum-iridium, gold, or stainless steel. In some variations, thestimulus is a biphasic pulse waveform. In some of these variations, thebiphasic pulse waveform is symmetrical. In some of these variations, thefrequency of the biphasic pulse waveform is between 20 Hz and 80 Hz. Insome variations, the stimulator probe is releasably connected to thestimulator body. In some of these variations, the device comprises adisabling mechanism that prevents stimulus delivery to the subject whenthe stimulator probe is reconnected to the stimulator body after beingdisconnected from the stimulator body. Additionally or alternatively,the device may comprise a lockout mechanism that prevents the stimulatorprobe from being reconnected to the stimulator body after beingdisconnected from the stimulator body. In some variations, thestimulator body is reusable and the stimulator probe is disposable. Insome variations, the device further comprises a detachable protectivecap. In some variations, the device further comprises a user interface.In some of these variations, the user interface comprises one or moreoperating mechanisms to adjust one or more parameters of the stimulus.Additionally or alternatively, the user interface may comprise one ormore feedback elements.

In some variations, the systems described here comprise systems forstimulating nasal tissue of a subject. In some variations, the systemcomprises a stimulator comprising a stimulator probe comprising a nasalinsertion prong and a stimulator body comprising a rechargeable powersource and a control subsystem to control a stimulus to be delivered tothe subject via the nasal insertion prong, and a base station torecharge the rechargeable power source. In some of these variations, thestimulator comprises memory to store data, and the base station isconfigured to retrieve data from the stimulator. Additionally oralternatively, the stimulator probe is removably connectable to thestimulator body, and wherein the stimulator probe blocks access to therechargeable power source when connected to the stimulator body.

In some variations, the methods described here comprise methods of tearproduction in a subject. In some variations, the method comprisespositioning a probe in contact with the nasal mucosa of the subject, anddelivering a stimulus via the probe to produce tears. In some of thesevariations, the method further comprises positioning a second probe incontact with the nasal mucosa of the subject. In some variations, thestimulus is electrical. In some of these variations, the stimulus isdelivered for a 5 minute period, and the Schirmer score over the 5minute period is at least 3 mm greater than a basal Schirmer score ofthe patient. In some of these variations the Schirmer score over the 5minute period is at least 5 mm greater than a basal Schirmer score ofthe patient. In some of these variations, the stimulus is a biphasicpulse waveform. In some of these variations, the biphasic pulse waveformis symmetrical. In some variations, the stimulus is pulsed. In somevariations, the method further comprises positioning a probe in contactwith the nasal mucosa of the subject and delivering a stimulus via theprobe to produce tears on a second occasion. In some variations, thestimulus is mechanical. In some variations, the stimulus is chemical.

In some variations, the methods described here comprise methods ofimproving ocular health in a patient. In some variations, the methodscomprise positioning a probe in a nasal cavity of the patient, anddelivering stimulation to the nasal tissue of the patient via the probeat least once daily during a treatment period comprising at least 2 daysto improve the ocular health of the patient, wherein improved ocularhealth is measured by decreased dry eye symptoms. In some of thesevariations, the probe comprises at least one electrode, and thestimulation is electrical. In some of these variations, decreased dryeye symptoms are measured by the Ocular Surface Disease Index, and theOcular Surface Disease Index decreases by at least 10% within thetreatment period, wherein the treatment period comprises 7 days. In someof these variations, the Ocular Surface Disease Index decreases by atleast 20% within the treatment period. In some variations, decreased dryeye symptoms are measured by the Ocular Surface Disease Index, and theOcular Surface Disease Index decreases by at least 40% within thetreatment period, wherein the treatment period comprises 90 days. Insome of these variations, the Ocular Surface Disease Index decreases byat least 50% within the treatment period. In some variations, thestimulation activates the nasolacrimal reflex. In some variations, theprobe is positioned in contact with nasal mucosa of the patient. In somevariations, the probe is positioned in contact with the septum. In somevariations, the probe is positioned in contact with the columella. Insome variations, the probe is positioned in contact with the tissueadjacent to the interface between the nasal bone and the upper lateralcartilage. In some variations, the probe is positioned in contact withnasal mucosa of the patient. In some variations, the method furthercomprises positioning a second probe in a second nasal cavity of thepatient. In some variations, the probe comprises at least one electrode.In some of these variations, the electrical stimulation comprises abiphasic pulse waveform. In some of these variations, the biphasic pulsewaveform is symmetrical. In some of these variations, the frequency ofthe biphasic pulse waveform is between 20 Hz and 80 Hz. In others ofthese variations, the stimulation is mechanical. In others of thesevariations, the stimulation is chemical. In others of these variations,the stimulation is thermal.

In some variations, the methods described here comprise methods ofimproving ocular health in a patient. In some variations, the methodscomprise positioning a probe in a nasal cavity of the patient, anddelivering stimulation to the nasal tissue of the patient via the probeat least once daily during a treatment period comprising at least 2 daysto improve the ocular health of the patient, wherein improved ocularhealth is measured by decreased corneal staining or conjunctivalstaining. In some variations, the probe comprises at least oneelectrode, and the stimulation is electrical. In some of thesevariations, improved ocular health is measured by decreased cornealstaining, and corneal staining decreases by at least 10% within thetreatment period, wherein the treatment period comprises 7 days. In someof these variations, corneal staining decreases by at least 20% withinthe treatment period. In some variations, improved ocular health ismeasured by decreased corneal staining, and corneal staining decreasesby at least 50% within the treatment period, wherein the treatmentperiod comprises 90 days. In some of these variations, corneal stainingdecreases by at least 60% within the treatment period. In somevariations, improved ocular health is measured by decreased conjunctivalstaining, and wherein conjunctival staining decreases by at least 5%within the treatment period, wherein the treatment period comprises 7days. In some of these variations, conjunctival staining decreases by atleast 10% within the treatment period. In some variations, improvedocular health is measured by decreased conjunctival staining, andwherein conjunctival staining decreases by at least 30% within thetreatment period, wherein the treatment period comprises 90 days. Insome of these variations, conjunctival staining decreases by at least40% within the treatment period. In some variations, the stimulationactivates the nasolacrimal reflex. In some variations, the probe ispositioned in contact with nasal mucosa of the patient. In somevariations, the probe is positioned in contact with the septum. In somevariations, the probe is positioned in contact with the columella. Insome variations, the probe is positioned in contact with the tissueadjacent to the interface between the nasal bone and the upper lateralcartilage. In some variations, the probe is positioned in contact withnasal mucosa of the patient. In some variations, the method furthercomprises positioning a second probe in a second nasal cavity of thepatient. In some variations, the probe comprises at least one electrode.In some of these variations, the electrical stimulation comprises abiphasic pulse waveform. In some of these variations, the biphasic pulsewaveform is symmetrical. In some of these variations, the frequency ofthe biphasic pulse waveform is between 20 Hz and 80 Hz. In others ofthese variations, the stimulation is mechanical. In others of thesevariations, the stimulation is chemical. In others of these variations,the stimulation is thermal.

In some variations, the methods described here comprise methods ofimproving ocular health in a patient. In some variations, the methodscomprise positioning a probe in a nasal cavity of the patient, anddelivering stimulation to the nasal tissue of the patient via the probeat least once daily during a treatment period comprising at least 2 daysto improve the ocular health of the patient, wherein improved ocularhealth is measured by increased tear production. In some of thesevariations, the probe comprises at least one electrode, and thestimulation is electrical. In some of these variations, increased tearproduction is measured by increased basal tear production, and basaltear production increases by at least 1 mm on the Schirmer Tear Testwithin the treatment period, wherein the treatment period comprises 7days. In some of these variations, basal tear production increases by atleast 2 mm on the Schirmer Tear Test within the treatment period. Insome variations, increased tear production is measured by increasedbasal tear production, and basal tear production increases by at least 2mm on the Schirmer Tear Test within the treatment period, wherein thetreatment period comprises 90 days. In some of these variations, basaltear production increases by at least 3 mm on the Schirmer Tear Testwithin the treatment period. In some variations, the stimulationactivates the nasolacrimal reflex. In some variations, the probe ispositioned in contact with nasal mucosa of the patient. In somevariations, the probe is positioned in contact with the septum. In somevariations, the probe is positioned in contact with the columella. Insome variations, the probe is positioned in contact with the tissueadjacent to the interface between the nasal bone and the upper lateralcartilage. In some variations, the method further comprises positioninga second probe in a second nasal cavity of the patient. In somevariations, the probe comprises at least one electrode. In some of thesevariations, the electrical stimulation comprises a biphasic pulsewaveform. In some of these variations, the biphasic pulse waveform issymmetrical. In some of these variations, the frequency of the biphasicpulse waveform is between 20 Hz and 80 Hz. In others of thesevariations, the stimulation is mechanical. In others of thesevariations, the stimulation is chemical. In others of these variations,the stimulation is thermal.

In some variations, the methods described here comprise methods ofimproving ocular health in a patient. In some variations, the methodscomprise positioning a probe in a nasal cavity of the patient, anddelivering stimulation to the nasal tissue of the patient via the probeat least once daily during a treatment period comprising at least 2 daysto improve the ocular health of the patient, wherein improved ocularhealth is measured by at least two of decreased Ocular Surface DiseaseIndex, decreased corneal staining, decreased conjunctival staining,increased basal tear production, and increased acute tear production. Insome of these variations improved ocular health is measured by at leastthree of decreased Ocular Surface Disease Index, decreased cornealstaining, decreased conjunctival staining, increased basal tearproduction, and increased acute tear production. In some of thesevariations, ocular health is measured by at least four of decreasedOcular Surface Disease Index, decreased corneal staining, decreasedconjunctival staining, increased basal tear production, and increasedacute tear production.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B, 1C, 1D, 1E show perspective, front, back, cut-away back,and cut-away side views, respectively, of an illustrative variation of ahandheld stimulator.

FIG. 2 shows a block diagram schematically representing a variation of astimulator.

FIG. 3A and FIGS. 3B-3C show perspective view and exploded views,respectively, of a stimulator body suitable for the handheld stimulatorsdescribed here. FIG. 3D shows a perspective view of a portion of thestimulator body of FIGS. 3A-3C.

FIG. 4 shows a perspective view of another variation of a stimulatorbody suitable for the handheld stimulators described here.

FIG. 5 shows a perspective view of another variation of a stimulatorbody suitable for the handheld stimulators described here.

FIGS. 6A, 6B, 6C, 6D, and FIGS. 6E-6F depict back, side, cut-away back,cut-away top, and perspective views, respectively, of a stimulator probesuitable for the handheld stimulators described here. FIG. 6G depicts aperspective view of a rigid support of the stimulator probe of FIGS.6A-6F.

FIGS. 7A, 7B, and 7C depict back, front, and perspective views,respectively, of a stimulator probe suitable for the handheldstimulators described here.

FIGS. 8A, 8B, and 8C depict back, front, and perspective views,respectively, of a stimulator probe suitable for the handheldstimulators described here.

FIG. 9A shows a perspective view of a stimulator probe suitable for thehandheld stimulators described here. FIG. 9B shows an exploded view ofthe stimulator probe of FIG. 9A without sleeves. FIG. 9C shows anassembled view of the stimulator probe of FIG. 9A without sleeves andwithout a first plate. FIGS. 9D-9F show perspective, side cut-away, andcross-sectional views of a sleeve of the stimulator probe of FIG. 9A.

FIGS. 10A, 10B, and 10C show perspective, back cut-away, and side views,respectively, of a stimulator probe suitable for the handheldstimulators described here.

FIG. 11A depicts a perspective view of a variation of a stimulator probesuitable for the handheld stimulators described here. FIG. 11B shows onemanner in which the stimulator probe of FIG. 11A may be constructed.

FIGS. 12A and 12B show perspective and cut-away top views, respectively,of a variation of a stimulator probe suitable for the handheldstimulators described here. FIG. 12C shows a cross-sectional view of thestimulator probe of FIGS. 12A-12B positioned in the nose of a user.

FIGS. 13A and 13B show perspective and cut-away perspective views,respectively, of a variation of a stimulator probe suitable for thehandheld stimulators described here.

FIG. 14 depicts a perspective view of a variation of a stimulator probesuitable for the handheld stimulators described here.

FIG. 15A depicts a perspective view of the stimulator of FIGS. 1A-1Ewith the stimulator probe disconnected from the stimulator body. FIGS.15B-15C illustrate an example of one mechanism for measuring how long astimulator probe has been connected to the stimulator body.

FIGS. 16A and 16B show side views of other variations of handheldstimulators.

FIGS. 17A-17E show an example of a handheld stimulator comprising amechanical fuse.

FIG. 18 illustrates a schematic diagram of stimulator circuitry.

FIGS. 19A and 19B show perspective and front views, respectively, of thehandheld stimulator of FIGS. 1A-1E with an attached cap. FIG. 19C showsa perspective view of a cap.

FIG. 20 shows a perspective view of the handheld stimulator of FIGS.9A-9F with an attached cap.

FIGS. 21A-21D depict portions of a stimulator system comprising astimulator and a base station. FIG. 21A shows a front view of thestimulator body docked in the base station, while FIGS. 21B, 21C, and21D depict side, back, and top views, respectively, of the base station.

FIGS. 22A-22D depict portions of another variation of a stimulatorsystem comprising a stimulator and a base station. FIG. 22A shows afront view of the stimulator body docked in the base station, whileFIGS. 22B, 22C, and 22D show top, bottom, and side views, respectively,of the base station.

FIGS. 23A-23B show another variation of a stimulator system comprising astimulator and a base station. FIG. 23A shows perspective views of thebase station and an undocked stimulation, while FIG. 23B shows aperspective view of the stimulator body docked in the base station.

FIG. 24 shows a cut-away side view of a variation of an implantablestimulator.

FIG. 25 shows a cross-sectional view of an implantable stimulatorpositioned in the nasal cavities.

FIG. 26A shows perspective view of a stimulator probe of an implantablestimulator.

FIG. 26B shows a perspective view of the stimulator probe of FIG. 26Aimplanted in the nasal cavities. FIG. 26C shows a perspective view ofthe stimulator probe of FIG. 26A connected to a stimulator body.

FIGS. 27A-27B and FIGS. 27C-27D depict side and front views,respectively, of a variation of an implantable stimulator. FIG. 27Eshows the stimulator of FIGS. 27A-27D positioned in the nasal cavities.

FIG. 28 shows one variation of a delivery device suitable for use withthe implantable stimulators described here.

FIG. 29A shows patients' average basal Schirmer scores over time with atreatment regimen as described here. FIG. 29B shows patients' averageacute Schirmer scores over time with a treatment regimen as describedhere. FIG. 29C shows comparative Schirmer score data.

FIG. 30 shows patients' average dry eye symptoms over time with atreatment regimen as described here.

FIG. 31A shows patients' average Ocular Surface Disease Index scoresover time with a treatment regimen as described here. FIG. 31B showscomparative OSDI data.

FIG. 32A shows patients' average normalized corneal staining over timewith a treatment regimen as described here. FIG. 32B shows comparativecorneal staining data.

FIG. 33A shows patients' average normalized conjunctival staining overtime with a treatment regimen as described here. FIG. 33B showscomparative conjunctival staining data.

FIGS. 34A-34C illustrate relevant anatomical locations.

FIGS. 35A-35B depict cut-away front and side views, respectively, of ahandheld stimulator configured to deliver one or more chemical agents.

FIG. 36A depicts a perspective view of a stimulator in a case. FIG. 36Bdepicts a perspective view of a stimulator and a case for thestimulator.

DETAILED DESCRIPTION OF THE INVENTION

Described here are devices, systems, and methods for treating one ormore conditions (such as dry eye) by providing stimulation to nasal orsinus tissue. Generally, the devices and systems may be configured tostimulate nasal or sinus tissue. The devices may be handheld orimplantable. In some variations, the devices may comprise a stimulatorbody and a stimulator probe, where the stimulator probe comprises one ormore nasal insertion prongs. The stimulus delivered by the stimulatorsdescribed here may in some variations be electrical; in othervariations, they may be mechanical, thermal, chemical, light-based,magnetic, or the like. When the devices and systems are used to treatdry eye, the methods may comprise stimulating nasal or sinus tissue toincrease tear production, reduce the symptoms of dry eye, or improveocular health.

Handheld Stimulators

Some variations of the stimulation systems described here may comprise ahandheld stimulator. FIGS. 1A, 1B, 1C, 1D, 1E show perspective, front,back, cut-away back, and cut-away side views, respectively, of anillustrative variation of a handheld stimulator 100, respectively. FIG.2 shows a block diagram schematically representing the stimulator 100.As shown in FIGS. 1A-1E, the stimulator 100 may comprise a stimulatorbody 102 and a stimulator probe 104. Generally, the stimulator body 102may be configured to generate a stimulus that may be delivered to thesubject. The stimulator body 102 may comprise a front housing 138, backhousing 140, and proximal housing 142, which may fit together to definea body cavity 154. The body cavity 154 may contain a control subsystem136 and a power source 152, which together may generate and control thestimulus.

The stimulus may be delivered to a subject via the stimulator probe 104.In some variations the stimulator body 102 and stimulator probe 104 maybe reversibly attachable, as described in more detail below. In othervariations, the stimulator probe may be permanently connected to thestimulator body. Some or all of the stimulator 100 may be disposable. Invariations where the stimulator body is permanently attached to thestimulator probe, the entire stimulator may be disposable. In othervariations, one or more portions of the stimulator 100 may be reusable.For example, in variations where the stimulator probe 104 is releasablyconnected to the stimulator body 102, the stimulator body 102 may bereusable, and the stimulator probe 104 may be disposable andperiodically replaced, as described in more detail below.

The stimulator probe 104 may comprise at least one nasal insertionprong, which may be configured to be at least partially inserted intothe nasal cavity of a subject or patient. In the handheld stimulatorvariation shown in FIGS. 1A-1E, the stimulator probe 104 may comprisetwo nasal insertion prongs 106 and 108. The stimulator probe 104 mayfurther comprise ridges 120, which may allow the patient to more easilygrip the probe 104.

In some variations, the stimulus may be electrical. In these instances,each nasal insertion prong may comprise at least one electrode. Asshown, the probe 104 may comprise a first electrode 110 on nasalinsertion prong 106 and a second electrode 112 on nasal insertion prong108. As shown in the cut-away view of the stimulator 100 in FIG. 1D, theelectrodes 110 and 112 may be connected to leads 130 and 132 locatedwithin prongs 106 and 108, respectively. The leads 130 and 132 may inturn be connected to connectors 122 and 124, respectively. Connectors122 and 124 may extend through lumens 208 and 210 in the proximalhousing 142, and may connect directly or indirectly to the controlsubsystem 136 and power source 152. As such, the electrical stimulus maytravel from the control subsystem 136 through the connectors 122 and124, through the leads 130 and 132, and through the electrodes 110 and112.

The stimulator body 102 may comprise a user interface 230 comprising oneor more operating mechanisms to adjust one or more parameters of thestimulus, as described in more detail below. The operating mechanismsmay provide information to the control subsystem 136, which may comprisea processor 232, memory 234, and/or stimulation subsystem 236. In somevariations, the operating mechanisms may comprise first and secondbuttons 114 and 116. In some variations, pressing the first button 114may turn on the stimulator and/or change one or more parameters of thestimulus (e.g., increase the intensity of the stimulus, change thestimulation pattern, or the like), while pressing the second button 116may turn off the stimulator and/or change one or more parameters of thestimulus (e.g., decrease the intensity of the stimulus, change thestimulation pattern, or the like). Additionally or alternatively, theuser interface may comprise one or more feedback elements (e.g., basedon light, sound, vibration, or the like). As shown, the user feedbackelements may comprise light-based indicators 118, which may provideinformation to the user, as described in more detail below.

Stimulator Body

As described briefly above, the stimulator body may comprise a housing,a user interface, a control subsystem, and a power source.

Housing

FIG. 3A and FIGS. 3B-3C show a perspective view and exploded views,respectively, of the stimulator body 102. The stimulator body 102 mayhave any suitable shape. In some variations, it may be desirable for thestimulator body 102 to be shaped such that it can be easily gripped by auser, such that it can be held with one hand, such that it can be placedupright on a surface, and/or such that it can be easily and/ordiscretely carried in a pocket or purse. As shown in FIG. 3A, thestimulator body 102 may have a truncated ovoid shape. However, it shouldbe appreciated that the stimulator body may have other shapes. Forexample, as shown in FIG. 4, a stimulator body 402 may have a flatproximal end and a rounded distal end. As another example, as shown inFIG. 5, a stimulator body 502 may have a generally rectangular shape,with rounded corners and a tapered proximal end. In other variations,the stimulator body may have a rectangular shape, a rounded rectangularshape, a circular shape, a cylindrical shape, a triangular shape, ateardrop, or the like, each of which may or may not be truncated. Theproximal end of the stimulator body 102 (formed by proximal housing 142)may have a shape that is complementary to the bottom of the stimulatorprobe 104, as described in more detail below.

As mentioned above, the stimulator body may comprise a housing formed bya front housing 138, a back housing 140, and a proximal housing 142.These may fit together to form the exterior of the stimulator body. Thefront housing 138 and back housing 140 may fit together with anysuitable attachment mechanism. For example, the front 138 and back 140housings may fit together with a tongue-and-groove joint. The proximalhousing 142 may comprise a proximal portion 204, which may fit over theproximal ends of the front and back housings 138 and 140, and a distalportion 206, which may fit within a portion of the stimulator probe 104,as described in more detail below. The housing formed by the front 138,back 140, and proximal 142 housings may comprise any number of suitableopenings for elements of the stimulator body. For example, the proximalhousing 142 may comprise two lumens 208 and 210 that may be configuredto receive connectors 122 and 124, described in more detail below. Thefront housing 138 may comprise an opening configured to receive aportion of the user interface 230, described in more detail below. Itshould be appreciated that while the housing is described here ascomprising front, back, and proximal housings, the housing may beconstructed from any number of separate housing components (e.g., two,three, four, five, or more).

In some instances, it may be desirable for the stimulator body to besealed, such that it may be waterproof or the like. In some of theseinstances, when the housing comprises a front housing 138, back housing140, and proximal housing 142, the three housing portions may attach soas to be watertight. For example, the tongue-and-groove joint describedabove may be watertight. In some variations, the stimulator body 102 mayfurther comprise one or more seals located at the interface between thefront housing 138 and the back housing 140, and/or between the front 138and back 140 housings and the proximal housing 142. In variations inwhich the housing comprises openings for other elements of thestimulator body (e.g., connectors 122 and 124, a release mechanism, orthe like), the interface between those elements and the stimulatorhousing may be watertight, and/or may comprise seals.

In some variations, it may be desirable for each of the front housing138, back housing 140, and proximal housing 142 to be formed from thesame material in order to improve the ability of the front housing 138,back housing 140, and proximal housing 142 to maintain a tight seal andto exhibit similar expansion/contraction properties with changes intemperature. In some variations, the front housing 138, back housing140, and top housing 142 may each comprise a rigid material, such as arigid plastic. For example, the front 138, back 140, and top 142housings may comprise a thermoplastic such as acrylonitrile butadienestyrene (ABS), polycarbonate, polyetherimide (e.g., Ultem™). However,the housing may comprise any suitable material or materials.Furthermore, it should be appreciated that in some variations the fronthousing 138, back housing 140, and/or proximal housing 142 may comprisedifferent materials.

In some variations the housing may comprise an alignment mechanism. Thealignment mechanism may assist in aligning the stimulator body with thestimulator probe in variations in which the stimulator body andstimulator probe are detachable, and/or it may assist in keeping thestimulator body and stimulator probe connected. Additionally oralternatively, in which the stimulator system comprises a base station(as described in more detail below), it may assist in aligning thestimulator body with the base station in variations and/or it may assistin keeping the stimulator body and the base station connected. Invariations in which the stimulator is configured to be attached to acharging cable, the alignment mechanism may assist in aligning thestimulator or a portion of the stimulator with a charging cable and/orkeeping the stimulator and charging cable attached. In some variations,the alignment mechanism may comprise a magnet. FIG. 3D shows aperspective view of a portion of the stimulator body 102. A magnet 134may be connected to the interior surface of the proximal housing 142 asshown. In other variations, a magnet may be connected to the interior ofanother portion of the housing, or to the exterior of any portion of thehousing. In variations in which the magnet 134 may assist in aligningthe stimulator body 102 with the stimulator probe 104, the stimulatorprobe 104 may comprise a magnet or ferromagnetic material in acorresponding location. In variations in which the magnet 134 may assistin aligning the stimulator body 102 to a base station, the base stationmay comprise a magnet or ferromagnetic material in a correspondinglocation, as described in more detail below.

In some variations the housing may comprise a weight. It may in someinstances be desirable for the stimulator to have a sufficient weightsuch that it has a substantial feel when held by a user. In somevariations, the alignment mechanism (e.g., a magnet) may further serveas a weight. Additionally or alternatively, the weight may comprise adense material or materials (e.g., iron or steel). The weight may belocated in any suitable location within the housing. In some instances,the weight may be attached to the interior of the housing, to a printedcircuit board comprising the control subsystem (described in more detailbelow), or threaded within pins holding a printed circuit board in place(e.g. pins 144 in stimulator body 102).

In some variations, the stimulator bodies described here may comprisefeatures to assist the user in holding the device. For example,stimulator 402 shown in FIG. 4 may comprise ridges 410 on both sides ofthe stimulator body 402. These ridges 410 may act as grips for the userto hold onto. It should be appreciated that any of the stimulator bodies(e.g., stimulator body 102) described here may comprise any suitablefeatures to assist the user in holding the device, such as anytexturized surface, a high-friction material (e.g., rubber),indentations, or the like.

User Interface

In instances where the stimulators described here comprise a userinterface, the user interface may comprise one or more operatingmechanisms, which may allow the user to control one or more functions ofthe stimulator. For example, the operating mechanisms may allow the userto power the device on or off, start or stop the stimulus, change theintensity of the stimulus, change the duration of the stimulus, changethe stimulus pattern, or the like. In some variations, the operatingmechanisms may be able to activate or deactivate different functions,and/or may be able to change different parameters, based on their mannerof operation (e.g., pressing a button briefly, pressing a button for aprolonged period, pressing a button with a particular pattern ofpressing actions, rotating a dial by different angles or differentspeeds). Each of the one or more operating mechanisms may be anysuitable structure, such as but not limited to a button, slider, lever,touch pad, knob, or deformable/squeezable portion of the housing, and astimulator may comprise any combination of different operatingmechanisms.

In one variation, the one or more operating mechanisms may comprise oneor more buttons. The stimulator body 102, for example, may comprise twobuttons 114 and 116. In the variation shown, the two buttons 114 and 116may be located on a single a flexible membrane 212. The flexiblemembrane 212 may comprise any suitable material or materials, such asbut not limited to a flexible polymer, such as a thermoplastic elastomer(e.g., a thermoplastic elastomer alloy (e.g., Versaflex™), thermoplasticpolyurethane, or the like), silicone, or the like. In some variations inwhich the flexible membrane is located within the front housing 138, theflexible membrane 212 may be attached to the front housing 138 such thatthey are chemically bound. In some variations, they may be connected viaovermolding, transfer molding, or two-shot molding. However, it shouldbe appreciated that the flexible membrane 212 may be attached to thehousing in any other suitable manner, such as via bonding.

The flexible membrane 212 may be separated into two buttons 114 and 116by a divider 150. As shown in FIGS. 1E and 3C, the divider 150 mayextend interiorly into the body cavity 154 from the interior surface ofthe flexible membrane 212. The end of the divider 150 may press againsta fixed surface within the body cavity 154 of the stimulator body 154.For example, the end of the divider 150 may press against a portion ofthe printed circuit board (PCB) (128) that forms the control subsystem136, described in more detail below. The divider 150 may thus serve asan inflection point on the flexible membrane 212, such that each of thetwo buttons 114 and 116 may be pressed separately by the user. Thedivider 150 may also serve to resist separation between the flexiblemembrane 212 and the housing (e.g., by breaking the adhesion between thehousing and the flexible membrane) by limiting the movement of theflexible membrane 212 into the body cavity 154.

If the user presses one of buttons 114 or 116, the movement of thebutton may be transferred to the control subsystem 136. As shown in FIG.3C, the interior surface of the flexible membrane 212 may comprise tworaised surfaces 214 and 216 on the interior surface of buttons 114 and116, respectively. When button 114 or 116 is depressed, thecorresponding raised surface 214 or 216 may press against PCB button 146or 148 (shown in FIG. 3D), respectively, located in the printed circuitboard 128, in order to transmit information to the control subsystem136. While the stimulator body 102 is shown as having two buttons formedon a single flexible membrane, it should be appreciated that in othervariations, two or more buttons may be separately formed. An example ofsuch buttons is shown in FIG. 4, which shows separate first and secondbuttons 404 and 406.

In stimulator body 102, pressing the top button 114 may power on thestimulator 100 when the stimulator 100 is off. In some variations inwhich the stimulator is capable of differing stimulus intensities, thestimulator may be powered on to the last stimulus intensity from beforethe stimulator was powered off. When the stimulator 100 is on, pressingthe top button 114 may increase the intensity of the stimulus (forexample, when the stimulus is electrical, pressing the top button 114may increase the amplitude of the stimulus waveform). Conversely,pressing the bottom button 116 may decrease the intensity of thestimulus (for example, when the stimulus is electrical, pressing thebottom button 116 may decrease the amplitude of the stimulus waveform).Pressing the bottom button 116 also may in some instances power off thestimulator 100. For example, pressing and holding the bottom button 116may power off the stimulator 100; or additionally or alternatively,pressing the bottom button 116 when the stimulus intensity is at itslowest level may power off the stimulator 100. However, it should beappreciated that additionally or alternatively, the stimulator 100 maypower off without user input (e.g., after a period of idle time). Insome variations, the stimulator 100 may provide feedback to the user toindicate that the buttons are being pressed (or that other operatingmechanisms are being operated). For example, pressing the buttons oroperating any of a stimulator's operating mechanisms may be accompaniedby a sound, vibration, tactile click, light, or the like, but need notbe.

The operating mechanisms of the stimulators described here may have anynumber of other suitable configurations. For example, in anothervariation of the stimulator body 502 shown in FIG. 5, the stimulatorbody 502 may comprise a button 504 and a ring-shaped slider 506. Thebutton 504 may be pressed to perform one or more stimulator functions(e.g., powering the device on or off, starting and stopping stimulation,as described in more detail regarding stimulator 100), and thering-shaped slider 506 may be rotated to perform one or more stimulatorfunctions (e.g., changing intensity of the stimulation, changing theduration of the stimulation, as described in more detail regardingstimulator 100).

In some variations, the stimulators may be configured to providefeedback or otherwise convey information to a user. This may be donevisually, audibly, or via tactile feedback. For example, the userinterface of the stimulator may comprise one or more light-based statusindicators (e.g., LEDs), which may light up to convey information to auser. The number and/or location of illuminated status indicators,and/or their color, may convey information to the user. For example, thenumber and/or locations of illuminated status indicators may indicatethe intensity of the stimulus or the charge or charging status of anyrechargeable battery; the color (e.g., red) of the illuminated statusindicator(s) may indicate a low battery or need to replace thestimulator probes (as explained in more detail below); and/or flashinglights may indicate that the stimulator is currently charging. Instimulator 100, the user interface 230 may comprise one or morelight-based status indicators 118. The light-based status indicators 118may comprise one or more light sources (e.g., LEDs) located on theprinted circuit board 128, which may be connected to or located nearlight-transmitting elements 158 on the front housing 138. Thelight-transmitting elements 158 may transmit light from a light sourceon the printed circuit board 128 to the exterior of the housing, whereit may be perceived by a user. In some variations, thelight-transmitting elements 158 may comprise fiber optics (e.g., lightpipes). In other variations, the light-transmitting elements 158 maycomprise translucent or transparent epoxy) in the front housing 138.While the light-based status indicators 118 are shown as being locatedon front housing 138, it should be appreciated that they may be in anysuitable location, such as on the back housing 140, the top housing 142,or the stimulator probe 104.

Additionally or alternatively, in some variations the stimulator bodymay comprise a display, which may be configured to convey information toa user via text and/or images. Additionally or alternatively, thestimulator body may comprise a speaker or buzzer configured to produceone or more speech prompts or other sounds. Additionally oralternatively, the stimulator body may be configured to vibrate. Whenthe stimulator body is configured to vibrate, the duration and/orrepetition of the vibration may convey information to the user. Itshould be appreciated that when the stimulator is configured to delivera mechanical stimulus (e.g., vibration), as described in more detailbelow, vibration and/or noise caused by the mechanical stimulus deliverymay be used to convey information to the user.

It should be appreciated that while the user interfaces described aboveare located on the stimulator bodies (e.g., stimulator body 102), inother variations, all of a portion of the user interface of thestimulator may be located on the stimulator probe. Additionally oralternatively, all or a portion of the user interface may be located ona separate unit, which may be physically or wirelessly attached to thestimulator. For example, in variations where the stimulator isconfigured to connect to a computer or mobile device (such as cellulartelephone, tablet, wearable computer (e.g., optical head-mounteddisplays such as Google Glass™), or the like, as will be discussed inmore detail below), the mobile device may act as a user interface. Forexample, the mobile device may act as a display to convey information tothe user or may allow the user to control or program the device.

Control Subsystem

Generally, the control subsystem may be configured to control a stimulusto be delivered to a subject via the stimulator probe. The controlsubsystem may be contained within the housing the stimulator. Thecontrol subsystem may be connected to the operating mechanisms of thestimulator (e.g., the buttons), which may allow the control subsystem toreceive input from a user. The control subsystem may also be connectedto mechanisms configured to provide feedback or otherwise conveyinformation to a user. In some variations, such as stimulator 100, thecontrol subsystem 136 may be located on a printed circuit board 128.When the control subsystem 136 is located on a printed circuit board128, the printed circuit board 128 may be fixed within the body cavity154 of the stimulator body 102 in any suitable manner. In somevariations, the printed circuit board 128 may be held in place relativeto the housing by pins 144. As shown in FIG. 3B, the interior surface ofback housing 140 may comprise four pins 144. The pins 144 may beconfigured to fit through corresponding openings 156 in the printedcircuit board 128, and may be further configured to fit into receivingrecesses 238 in the front housing 138. It should be appreciated that inother variations in which the printed circuit board is secured by pins,the housing may comprise any number of pins 144, which may be located onany portion of the housing.

The control subsystem 136 may include any circuitry or other componentsconfigured to operate the stimulators as described here. In somevariations the control subsystem may comprise a processor 232, memory234, and/or a stimulation subsystem 236. Generally, the processor may beconfigured to control operation of the various subsystems of the controlsubsystem. For example, the processor 232 may be configured to controlthe stimulation subsystem 236 to control parameters of the stimulationprovided by the stimulation subsystem 236. The memory 234 may beconfigured to store programming instructions for the stimulator, and theprocessor 232 may use these programming instructions in controllingoperation of the stimulator. The stimulation subsystem 236 may beconfigured to generate a stimulation signal and deliver the stimulationsignal to a patient via the stimulator probe. In other variations, thecontrol subsystem 136 may comprise a finite state machine.

In some variations, the control subsystem 136 may comprise adetection/recording subsystem. In these variations, thedetection/recording subsystem may be configured to monitor one or moreparameters of a subject (e.g., subject impedance), the stimulationdelivered to the subject (e.g., date and time of stimulation, durationof the stimulation, amplitude of the stimulation signal, pulse width,frequency), and/or the stimulator itself (e.g., diagnostic data). Thedetection/recording subsystem may record some or all of this data to thememory. Additionally or alternatively, the control subsystem 136 may beconfigured to accept and record user input regarding subjectsymptomology, subject activity, or the like.

Additionally or alternatively, the control subsystem may comprise acommunications subsystem. The communication subsystem may be configuredto facilitate communication of data and/or energy between the stimulatorand an external source. For example, in some variations thecommunications subsystem may be configured to allow the stimulator tocommunicate wirelessly (e.g., via WiFi, Bluetooth, or the like) with anexternal device (e.g., an external programmer, base station, laptop orother computer, mobile device such as a mobile phone, tablet, wearablecomputer (e.g., optical head-mounted displays such as Google Glass™) orthe like), and may comprise an antenna, coil, or the like. Additionallyor alternatively, the communication subsystem may be configured tocommunicate with an external device (e.g., a flash drive, a laptop orother computer, a mobile device such as a mobile phone, palm pilot, ortablet, or the like) via a wired transmission line. In these variations,the stimulator may comprise one or more ports (e.g., a USB port),connectors and/or cables configured to physically connect the stimulatorto an external device, such that data and/or energy may be transmittedbetween the stimulator and the external device.

The control subsystem may in some variations comprise safety mechanisms,such as limits on the voltage, current, frequency, and duration of thestimulus when the stimulus is electrical. In some variations, some ofthese safety mechanisms may be part of the stimulation subsystem. Forexample, the stimulation subsystem 236 of the control subsystem 136 ofstimulator 100 may limit the voltage and current that may be deliveredto the patient. In some variations, the voltage may be limited by avoltage regulator. In some of these variations, the voltage limit may bebetween about 1 V and about 100 V. In some of these variations, thevoltage limit may be between about 5 V and 50 V, between about 10 V and25 V, or between about 15 V and 20 V. In some variations, the voltagemay be regulated via a boost regulator connected to the power source152, but it should be appreciated that any suitable voltage regulatormay be used. In some variations, the current may be limited by aresistor in series with the load or a current-limiting transistor, orany other suitable combinations of elements. In some variations, thecurrent limit may be about between about 1 mA to about 30 mA, betweenabout 5 mA to about 20 mA, or about 10 mA. In some variations, thestimulation subsystem 236 may be capacitively coupled by one or moreseries capacitors on the output. This capacitive coupling may prevent DCcurrents from being applied to the patient, and may limit the totalcharge injection and pulse duration.

Additionally or alternatively, some or all of the safety mechanisms ofthe control subsystem 136 may be part of the processor 232. For example,the processor 232 may comprise software that limits the frequency towithin an allowed range. In some variations, the frequency may belimited to between about between about 0.1 Hz and about 200 Hz, betweenabout 10 Hz and about 60 Hz, between about 25 Hz and about 35 Hz,between about 50 Hz and about 90 Hz, between about 65 Hz and about 75Hz, between about 130 Hz and about 170 Hz, between about 145 Hz andabout 155 Hz, or between about 145 Hz and about 155 Hz. Additionally oralternatively, the processor 232 may comprise software that limits thestimulus intensity (e.g., the current or voltage). In some of thesevariations, the voltage limit may be between about 5 V and 50 V, betweenabout 10 V and 25 V, or between about 15 V and 20 V. In some variations,the current limit may be about between about 1 mA to about 30 mA,between about 5 mA to about 20 mA, or about 10 mA. The processor 232 mayadditionally or alternatively comprise software that limits the stimulusduration. In some variations, the duration may be limited to about 1minute, about 2 minutes, about 3 minutes, about 5 minutes, about 10minutes, or the like. In some variations in which the stimulator probe104 is removably connected to the stimulator body 102, the controlsubsystem 136 may prevent the delivery of current by the stimulationsubsystem 236 when the stimulator probe 104 is disconnected from thestimulator body 102. For example, the control subsystem 136 may preventdelivery of current when the mechanism described with respect to FIGS.15B-15C does not detect an attached stimulator probe. Additionally oralternatively, the control subsystem 136 may prevent delivery of currentby the stimulation subsystem 236 when the stimulator probe 104 is not incontact with a patient's tissue.

Power Source

The stimulator may comprise a power source. The power source may be anysuitable power supply capable of powering one or more functions of thestimulator, such as one or more batteries, capacitors, or the like. Asshown in FIGS. 3C-3D, in some variations the power source may comprise alithium coin cell battery 152. The battery 152 may be secured in placevia any suitable method, such as a clip 160 attached to the printedcircuit board 128 comprising the control subsystem 136. In somevariations, the power source may be rechargeable, as described in moredetail below.

While the stimulator body 102 comprises a power source, in othervariations the stimulator body need not comprise a power source. In somevariations, the stimulator body may comprise a port, cord, or othermechanism for connecting the stimulator to an external power source(such as a wall outlet or separate battery pack), which in turn may beused to power one or more portions of the stimulator. In some othervariations, such a port, cord, or other mechanism may be used torecharge a rechargeable power source. The stimulator body 102 maycomprise such a port (e.g., a USB port) at any suitable location, suchas between the connectors 122 and 124 on the proximal housing 142, onthe back housing 140, on the front housing 138, or at the proximal endof the stimulator body 102 between the front 138 and back housings 140.

Stimulator Probe

The stimulator probe of the stimulator may comprise one or more nasalinsertion prongs, which may be configured to extend at least partiallyinto a nasal cavity of a subject. FIGS. 6A, 6B, 6C, 6D, and FIGS. 6E-6Fdepict back, side, cut-away back, cut-away top, and perspective views,respectively, of the stimulator probe 104 of stimulator 100. As shownthere, the stimulator probe 104 may comprise a first nasal insertionprong 106 and a second nasal insertion prong 108. The first and secondprongs 106 and 108 may be connected via a base member 126. The basemember 126 may be configured to hold at least a portion of the first andsecond prongs in fixed relation to each other.

Prongs & Base

The nasal insertion prongs 106 and 108 may generally be configured to beinserted a subject's nostrils. As shown in FIGS. 6A-6F, each nasalinsertion prong 106 and 108 may comprise an elongate portion 162 and164, respectively. Each elongate portion 162 and 164 may have at itsdistal end a distal portion 176 and 178. In some variations, the distalportions 176 and 178 may have a diameter (or greatest cross-sectionaldimension) that is larger than the diameter (or greatest cross-sectionaldimension) of the elongate portion 162 and 164 of the prongs proximal tothe distal portions. This may allow a portion of the distal portions 176and/or 178 (e.g., the electrodes, described below) to be brought intocontact with a subject's tissue, while the elongate portions 162 and 164are not in contact with the subject's tissue. For example, the diameterof the nasal insertion prongs 106 and 108 at the distal portions 176 and178 may in some instances be between about 3 mm and about 7 mm, whilethe diameter of the elongate portions 162 and 164 may be between about 1mm and about 6 mm proximal to the distal portions. More specifically, insome variations the diameter of the nasal insertion prongs at the distalportions 176 and 178 may be about 5 mm, and the diameter of the elongateportions 162 and 164 may be about 3 mm. The proximal portion of theelongate portions 162 and 164 may flare outward (i.e., have anincreasing diameter or greatest cross-sectional dimension) toward thebase member, which may in some variations act as a stop to limit thedistance that the nasal insertion prongs 106 and 108 may be advancedinto the nose of a user.

The first and second nasal insertion prongs 106 and 108 may be connectedto each other via a base member 126. In the variation shown in FIGS.6A-6F, the prongs 106 and 108 may be integrally formed with the basemember 126 by a rigid support 218 and a flexible overlay 220, as shownin FIG. 6C. The rigid support 218 may provide support to the base of thenasal insertion prongs 106 and 108 and may interface with the top of thestimulator body 102, as described in more detail below. The rigidsupport 218 may comprise any suitable material or materials, such as arigid plastic. For example, in some variations, the rigid support 218may comprise a thermoplastic such as acrylonitrile butadiene styrene(ABS), polycarbonate, polyetherimide (e.g., Ultem™). It may in someinstances be desirable for the rigid support 218 to comprise the samematerial as a portion of the stimulator body 102 (e.g., the proximalhousing 142 (described above)), in order to improve the ability toattach the stimulator probe 104 to the stimulator body 102, as describedin more detail below. In some variations, the rigid support 218 maycomprise a bottom portion 240 configured to interface with thestimulator body 102, and a top portion comprising one or more supports242 (e.g., as shown in FIG. 6G, three supports 242). The top portion mayfurther comprise two lumens 208 and 210, configured to receive leads asdescribed below. In some variations, the supports 242 may besaddle-shaped.

The flexible overlay 220 may form the nasal insertion prongs 106 and 108and may wrap around the rigid support 218 to form the base member 126.The flexible overlay 220 may comprise any suitable material ormaterials. The flexible overlay 220 may comprise a more flexiblematerial than the rigid support 218. For example, in some variations theflexible overlay 220 may comprise a flexible polymer, such as athermoplastic elastomer (e.g., thermoplastic elastomer alloys (e.g.,Versaflex™), thermoplastic polyurethanes, or the like), silicone, or thelike. Although the nasal insertion prongs 106 and 108 may be integrallyformed with the base member 126 in stimulator probe 104, in othervariations, the nasal insertion prongs may separately formed from thebase member, as shown for example in FIGS. 9A-9F, FIGS. 10A-10C, andFIG. 14, which are described in more detail below.

The base member 126 may allow the nasal insertion prongs 106 and 108 tobe manipulated as a single unit (and disposed as a single unit, ininstances where the stimulator probe is disposable). In some variations,the base member 126 may act as a stop to limit the distance that thenasal insertion prongs 106 and 108 may be advanced into the nose of auser. Additionally or alternatively, one or more of the nasal insertionprongs may include a flange or other mechanical stop to limit thedistance that the prongs may be inserted into a user's nose. The basemember 126 may further help to control the relative orientation of theprongs. For example, as shown in FIGS. 6A-6F, the two nasal insertionprongs 106 and 108 may be connected to the base member 126 such that thetwo prongs are oriented substantially parallel to each other. In somevariations, having the nasal insertion prongs oriented substantiallyparallel to each other may provide advantages in manufacturing and mayaid in nasal insertion.

However, in other variations, the nasal insertion prongs may not beoriented parallel to each other. For example, in some variations, thenasal insertion prongs may be angled toward each other. For example,FIGS. 7A-7C and FIGS. 8A-8C show variations of stimulator probessuitable for use with the stimulators described here. As shown in FIGS.7A-7C, stimulator probe 700 may comprise first and second nasalinsertion prongs 702 and 704, respectively, connected to a base member706. The nasal insertion prongs 702 and 704 may be connected to the basemember 706 such that they are angled toward each other. Similarly, asshown in FIGS. 8A-8C, stimulator probe 800 may comprise first and secondnasal insertion prongs 802 and 804, respectively, connected to a basemember 806 such that they are angled toward each other.

The two nasal insertion prongs may be positioned with any suitabledistance between them (e.g., between about 3 mm and about 15 mm). Insome variations, it may be desirable for the distance between the twonasal insertion prongs to be such that they fit simultaneously into eachof the user's nostrils on either side of the septum. Additionally oralternatively, it may be desirable for the distance to be such that thenasal insertion prongs are configured to self-align to the desiredstimulation location (described in more detail below) when inserted intothe user's nasal cavities. In some of these variations, the distancebetween the central longitudinal axes of the two nasal insertion prongs106 and 108 (labeled as distance “A” in FIG. 6A) may be between about 12mm and about 16 mm. The diameter of the nasal insertion prongs at thedistal portions 176 and 178 may in some instances be about 3 mm to about7 mm as described above, and thus the distance between the distalportions (labeled as distance “B” in FIG. 6A) may be about 5 mm to about11 mm. More specifically, in some variations the distance between thecentral axes of the two nasal insertion prongs 106 and 108 may be about14 mm, and the diameter of the nasal insertion prongs at the distalportions 176 and 178 may be about 5 mm, and thus the distance betweenthe distal portions may be about 11 mm.

The one or more nasal insertion prongs may have any suitable length. Insome variations, the length of the nasal insertion prongs may be suchthat when inserted into the nasal cavity, at least a portion (e.g.,distal portions 176 and 178) is capable of reaching the area of thenasal cavity that is desired to be stimulated. For example, the lengthof the nasal insertion prongs may be such that when inserted into thenasal cavity, at least a portion is capable of reaching the nasal mucosaor other area desired to be stimulated, as described in more detailbelow. In some variations, the length of the nasal insertion prongsextending from the base member (i.e., the farthest the nasal insertionprongs could be inserted into the nasal cavity) may be between about 25mm and about 45 mm. In other variations, the length of the nasalinsertion prongs extending from the base member may be between about 30mm and about 40 mm. For example, in some variations the nasal insertionprongs 106 and 108 may have a length extending from the base member 126of about 37.5 mm (labeled as distance “C” in FIG. 6A). While the twonasal insertion prongs of stimulator probe 104 are shown as having thesame fixed length, in other variations different prongs of a stimulatorprobe may different lengths. In some variations, one or more prongs mayhave an adjustable height. For example, in some of these variations, aprong may be configured to telescope to alter the height of the prong.In other variations, the prongs may be removable from the base member,and prongs having different lengths may be attached to the base member.Furthermore, while the prongs are shown as being substantially straight,it should be appreciated that in other variations the prongs maycomprise one or more bends or curves.

The nasal insertion prong dimensions and configuration described withrespect to stimulator probe 104 may allow the nasal insertion prongs 106and 108 to self-align to the desired stimulation location when insertedinto a user's nasal cavities. The length of the nasal insertion prongsis desirably long enough such that the prongs can reach the desiredstimulation location (e.g., the nasal mucosa superior to the columella,such as near the interface between the nasal bone and the upper lateralcartilage) in a range of patients. However, it should be appreciatedthat in some instances it may be desirable to stimulate the columella.For those patients having a larger distance between the columella andthe desired stimulation location, a longer portion of the nasalinsertion prongs may be inserted into the nasal cavities. For thosepatients having a shorter distance between the columella and the desiredstimulation location, a shorter portion of the nasal insertion prongsmay be inserted into the nasal cavities. Because the patient's nasalcavities may narrow from inferior to superior, as the nasal stimulationprongs are advanced superiorly into the nasal cavities toward thedesired stimulation location, the nasal tissue may generate a forcepressing the nasal insertion prongs medially. When the nasal insertionprongs comprise a flexible material (e.g., a flexible polymer, such as athermoplastic elastomer (e.g., a thermoplastic elastomer alloy (e.g.,Versaflex™), thermoplastic polyurethane, or the like), silicone, or thelike) as described herein, the nasal insertion prongs may flex medially,bringing them into contact with the desired stimulation location (e.g.,the nasal mucosa on or near the septum, such as on the septum near theinterface between the nasal bone and the upper lateral cartilage), asdescribed in more detail below.

In some variations, it may be desirable to have a particular flexibilityor range of flexibilities in order to allow the nasal insertion prongsto self-align to the desired stimulation location when inserted into auser's nasal cavities. In these variations, properties of the nasalinsertion prongs (e.g., the Young's modulus, thickness of the flexiblematerial or materials, the properties of the leads located within theprongs (described in more detail below)) may be chosen to allowself-alignment. Generally, it may be desirable for the prongs to bestiff enough such that they can be pushed into the nasal cavitieswithout buckling, while being flexible enough to self-align and/or to beatraumatic to the nasal tissue during regular use and insertion, and/orduring a sudden movement (e.g., a sneeze). This may also improve comfortfor the user. In some variations, the desired hardness of the materialmay be between about 40 D and about 90 D, between about 50 D and about80 D, between about 60 D and about 70 D, or about 65 D. In addition tohaving material properties that may be atraumatic to nasal tissue, itmay be desirable for the distal tips of the nasal insertion prongs tohave rounded edges to help minimize the risk of tissue damage duringadvancement of the prongs into the nose.

Electrodes

When the stimulators described here are configured to deliver anelectrical stimulus, at least one of the nasal insertion prongs maycomprise one or more electrodes configured to deliver a stimulus totissue. In variations where a stimulator comprises two nasal insertionprongs, each of the two nasal insertion prongs may comprise at least oneelectrode. Having multiple electrode-bearing prongs may allow thestimulator to provide bipolar stimulation (and/or bilateral stimulationof two nostrils), as will be discussed in more detail below.

When a nasal insertion prong or prongs of the stimulators describe herecomprise one or more electrodes, the electrodes may have any suitabledesign. In variations in which the electrodes comprise an arc of acylindrical surface, such as in the variation shown in FIGS. 6A-6F, theelectrodes 110 and 112 may comprise about a 100 degree arc of acylindrical surface. That is, openings 180 and 182 in the distalportions 176 and 178 of the nasal insertion prongs may comprise about a100 degree arc of a cylinder, and the electrodes 110 and 112 may belocated within the openings 180 and 182. In other variations, theelectrodes may be any suitable arc length of a cylinder. For example, insome instances, the electrodes may be semi-cylindrical, as shown inFIGS. 7A-7C, 11A-11B, and 12A-12C (discussed further below). As shown inFIGS. 12A-12C, for example, the stimulator probe 1200 may comprise afirst nasal insertion prong 1202 and a second nasal insertion prong 1204connected by a base member 1206, with each prong having an electrode1208. The electrodes 1208 may be semi-cylindrical. In other instances,the electrodes may be a partial cylinder having an arc greater than 100degrees (e.g., between about 110 degrees and about 270 degrees, about110 degrees, about 120 degrees, about 180 degrees, about 270 degrees, orthe like). In yet other instances, an electrode may be a partialcylinder having an arc less than 100 degrees (e.g., between about 30degrees about 95 degrees, about 90 degrees, about 45 degrees, or thelike).

Although the electrodes described above may comprise an arc of acylindrical surface, it should be appreciated that the electrodesdescribed here may have any suitable shape. In some other variations,for example, the electrodes may comprise two or more adjacent arcs of acylindrical surface. For example, the nasal insertion prongs 702 and 704of stimulator probe 700 may comprise two semi-cylindrical electrodes 708and 710 or 712 and 714, respectively. In yet other variations, theelectrodes may comprise a portion of an arc of a cylindrical surface,wherein the portion of the arc comprises rounded edges. As example isshown in FIGS. 8A-8C, which shows electrodes 808 and 810 of nasalinsertion prongs 802 and 804, respectively. In some other variations,for example, an electrode may be ellipsoid or spherical, ovoid, or thelike. In yet other variations, the electrodes may comprise an array ofelectrodes, as shown for example in FIGS. 13A-13B (described in moredetail below). In some variations, having an array of electrodes mayallow a stimulus to be delivered to tissue even if one or more of theelectrodes in the array fails, and/or may facilitate unilateralstimulation with a single nasal insertion prong.

When the nasal insertion prongs comprise one or more electrodes, thecenter of the electrodes may be angled relative to the axis intersectingthe first and second prongs. In some variations, the electrodes may beangled such that when the first nasal insertion prong is positioned in afirst nostril and the second nasal insertion prong is positioned in thesecond nostril, the electrodes may be directed toward the front of thenose. When an electrical stimulus is delivered through the electrodes ofthe first and second nasal insertion prongs and, the stimulation energymay be directed toward the front of the nose. This may allow forselective activation of nerves in the front of the septum and nasalmucosa, while minimizing activation of nerves toward the rear of thenasal septum. This may reduce negative side effects that may occur fromstimulation of nerves that innervate the teeth, as described in moredetail below. Specifically, in the variation of the stimulator probe104, as shown in FIG. 6D, the center of the electrode 110 of the firstnasal insertion prong 106 (shown by line 226) may be rotated at an angleθ₁ relative to the axis 166 intersecting the first 106 and second 108nasal insertion prongs, while the center of the electrode 112 of thesecond nasal insertion prong 108 (shown by line 228) may be rotated atan angle θ₂ relative to the axis 166. Similarly, in the variation of thestimulator probe 1200 shown in FIGS. 12A-12C, the center of theelectrode 1208 of the first prong 1202 (represented by line 1214) may berotated at an angle θ₃ relative to the axis 1212 intersecting the first1202 and second 1204 nasal insertion prongs, while the center of theelectrode 1210 of the second prong 1204 (represented by line 1216) maybe rotated at an angle θ₄ relative to the axis 1212.

The angles θ₁ and θ₂ of the stimulator probe 104, or 03 and 04 of thestimulator probe 1200, may be the same or different, and may be anysuitable value (e.g., about 45 degrees, about 90 degrees, about 180degrees, between about 0 degrees and about 90 degrees, between about 15and about 75 degrees, or the like). In some variations, the center ofthe electrodes may face each other (e.g., angles θ₁ and θ₂ or θ₃ and θ₄may be zero). In the variation shown in FIGS. 6D and 12B, the angles θ₁,θ₂, θ₃, and θ₄ may each be 45 degrees. As such, when the stimulatorprobe 104 or 1200 is positioned such that the first nasal insertionprong is positioned in a first nostril and the second nasal insertionprong is positioned in the second nostril, the electrodes may bedirected partially toward the front of the nose, as described in moredetail herein. For example, FIG. 12C shows electrodes 1208 positioned innostrils 1220 against septum 1222 and directed partially toward thefront of the nose.

The electrodes may be positioned on any suitable longitudinal portion orportions of the nasal insertion prongs. The position of the electrodealong the prong may at least partially determine the placement of theelectrode relative to tissue when the stimulator probe is advanced intothe nose. In some variations, an electrode may be located at anintermediate position along a prong of stimulator. For example, in thevariation of the stimulator probes depicted in FIGS. 6A-6F, theelectrodes 110 and 112 may be located at an intermediate position alongthe nasal insertion prongs, within the distal portions 176 and 178 theprongs but not at the distal tip of the prongs. The electrodes 110 and112 may be located any suitable distance from the distal tip of theprongs, such as between about 0.1 mm and about 4 mm, about 4 mm andabout 8 mm, or more than 8 mm from the distal dip of the prongs (e.g., 1cm from the distal tip). In some variations, the electrodes 110 and 112may be located about 2.5 mm from the distal tip of the prongs. In somevariations, the electrodes may be locate such that when inserted intothe nasal cavity, the electrodes are capable of reaching the nasalmucosa or other area desired to be stimulated. In some variations,distance from the base member of the stimulator probe to thelongitudinal center of the electrode (i.e., the farthest the center ofthe electrode could be inserted into the nasal cavity) may be betweenabout 25 mm and about 45 mm. In other variations, the distance from thebase member of the stimulator probe to the longitudinal center of theelectrode may be between about 30 mm and about 40 mm. For example, insome variations the distance from the base member of the stimulatorprobe to the longitudinal center of the electrode may be about 32.5 mm(labeled as distance “D” in FIG. 6A). The electrode may have anysuitable length, such as between about 1 mm and about 10 mm, betweenabout 3 mm and about 7 mm, about 5 mm, or more than about 10 mm.

In other variations, an electrode may be connected to a distal end of anasal insertion prong. In the variation of the stimulator probe 1400shown in FIG. 14 (described in more detail below), each of the first1402 and second 1404 nasal insertion prongs may comprise an electrode1414 and 1415, respectively, positioned at a distal end thereof.Generally, when the electrodes are positioned at the distal end of theprongs, it may be desirable to provide an electrode having no edges orrounded edges to help minimize the risk of tissue damage duringadvancement of the electrodes into the nose. For example, the sphericalelectrodes 1414 and 1415 may be relatively atraumatic to nasal or sinustissue as the first 1402 and/or second 1404 prongs are advanced into thenose.

The electrode(s) described here may be made from one or more conductivematerials. In some variations, the electrodes may comprise metals (e.g.,stainless steel, titanium, tantalum, platinum or platinum-iridium, otheralloys thereof, or the like), conductive ceramics (e.g., titaniumnitride), liquids, gels, or the like. In some variations, the electrodemay comprise one or more materials configured to promote electricalcontact between electrodes of the stimulator probe and tissue (i.e., allof an electrodes or a portion of the electrode, such as a covering). Insome instances, the impedance provided by tissue may be at leastpartially dependent on the presence or absence of fluid-like materials(e.g., mucous) in the nasal cavity. The material(s) may help to minimizethe impact of subject tissue impedance by providing a wet interfacebetween the electrode and tissue, which may act to normalize theimpedance experienced by the electrodes. This may in turn normalize theoutput and sensation experienced by the user.

In the variation shown in FIGS. 6A-6F, the electrode may comprise ahydrogel. In hydrogel may be any suitable hydrogel, including thehydrogels described in U.S. Provisional Patent Application No.61/944,340, filed on Feb. 25, 2014, and titled “Polymer Formulations forNasolacrimal Stimulation,” the contents of which are hereby incorporatedby reference in their entirety. The hydrogel may be located within theopenings 180 and 182 of the distal portions 176 and 178 of the nasalinsertion prongs 106 and 108. As described above, the hydrogel electrodemay form about a 100 degree arc of a cylinder, although it should beappreciated that the hydrogel electrode may in other variations haveother shapes (e.g., a smaller or larger arc, as described in detailherein). The hydrogel may fill the openings 180 and 182 and the adjacentportions of the central lumens 222 and 224 of the nasal insertionprongs. As such, the hydrogel may surround the axial portion of theleads (described in more detail below) located adjacent to the openings180 and 182. In some variations, the distal portions 176 and 178 of thenasal insertion prongs may further be covered by a thin hydrogel skin.The hydrogel skin may help to retain the hydrogel electrodes within thedistal portions 176 and 178 of the nasal insertion prongs 106 and 108.Additionally or alternatively, in variations having a hydrogel skin, thehydrogel skin may improve manufacturability (e.g., by allowing theelectrodes to be formed by dip coating). In some variations, the distalportions 176 and 178 of the nasal insertion prongs 106 and 108 maycomprise retention columns located between the surface of the electrodeand the central lumens 222 and 224. The retention columns may help toretain the leads within the central lumens, and when the electrodescomprise a hydrogel, may help to retain the hydrogel within the opening180 and 182.

In other instances, the electrodes may comprise one or more coveringsthat may be configured to connect to a stimulator probe to at leastpartially cover an electrode of the stimulator probe. In somevariations, the covers may comprise a hydrogel. In some variations, thecovers may comprise a foam or porous material which may be impregnatedwith a gel or liquid. Because the impedance provided by tissue may be atleast partially dependent on the presence or absence of fluid-likematerials, these covers may normalize the impedance experienced by theelectrodes. For example, in the variation of the stimulator probe 1400shown in FIG. 14, the stimulator probes 1402 and 1404 may comprise oneor more foam covers 1418, which may be configured to fit over and coverthe electrodes 1414 and 1415. The covers 1418 may comprise a foammaterial, which may be impregnated or otherwise filled with a conductiveliquid or gel. When placed in contact with dry nasal tissue, the gel orliquid may wet the nasal tissue to reduce the impedance of the tissue,which may result in a more consistent impedance experienced by theelectrodes 1415 and 1415. In some variations, the covers 1418 may bere-wettable to replace or replenish the gel or liquid. In othervariations, the electrodes may be coated with a hydrogel. However, itshould be appreciated that the electrodes need not comprise one or moresuch coverings to normalize impedance.

Leads

When a nasal insertion prong or prongs of the stimulators described herecomprise one or more electrodes, the electrodes may comprise leads. Whenthe stimulator probe is connected to a stimulator body, the leads maycontact the circuitry of the stimulator body to electrically connect theelectrodes to the stimulator body circuitry, as described in more detailbelow. As such, the leads may extend at least partially through each ofthe nasal insertion prongs. The leads may be formed from one or moreconductive materials (e.g., stainless steel, titanium, platinum orplatinum-iridium, other alloys thereof, or the like), conductiveceramics (e.g., titanium nitride), and may be positioned such that atleast a portion of each lead contacts a respective electrode to providea conduction pathway between the lead and the electrode.

The leads of stimulator probe 104 can be seen in the cut-away view inFIG. 6C. As shown there, the leads 130 and 132 may each comprise aspring. The springs comprising leads 130 and 132 may comprise anysuitable biocompatible conductive material or materials. For example, insome variations, the springs may comprise stainless steel. In othervariations, the springs may comprise gold or platinum. In somevariations, the springs may comprise two or more materials (e.g.,stainless steel with gold plating). The leads 130 and 132 may extendthrough the central lumens 222 and 224 of the nasal insertion prongs 106and 108, respectively. A portion of the leads (e.g., the distal ends)may contact the electrodes. For example, distal ends of the leads 130and 132 may extend through the hydrogel forming electrodes 110 and 112,as described in more detail herein. In variations in which the leadscomprise springs, the wound coil of the springs may allow for a greaterconductive surface between the leads and the hydrogel electrode ascompared to a single straight wire. Additionally or alternatively, thewound coil of the springs 130 and 132 may grip the hydrogel electrode,thus better retaining it within the distal portions 176 and 178 of thenasal insertion prongs 106 and 108. The proximal ends of the leads 130and 132 may extend through the lumens 208 and 210 through the rigidsupport 218, such that the proximal ends of the leads are able tocontact the circuitry of the stimulator body, as described in moredetail below. In variations in which the leads comprise springs, theproximal ends 184 and 186 of the springs may have a tighter pitch thanthe rest of the springs. This may create a more even surface to contactthe circuitry of the stimulator body. The spring force may also promotecontact between the leads and the circuitry of the stimulator body, asdescribed in more detail below. Additionally or alternatively, theproximal ends 184 and 186 may have a different (e.g., greater) coildiameter than the rest of the springs, which may also improve thecontact between the leads and a portion of the stimulator body.

It should be appreciated the leads need not comprise springs. In othervariations, for example, stimulator probes may comprise leads comprisinga conductive loop. An example is shown in FIGS. 9A-9F. As shown there, astimulator probe 900 may comprise a first 902 and a second 904 nasalinsertion prong, each comprising an electrode 914. The first 902 andsecond 904 nasal insertion prongs may be substantially parallel, and mayeach be attached to a base member 906. The first 902 and second 904nasal insertion prongs may each comprise a sleeve 924, described in moredetail below. As shown in the exploded view of FIG. 9B with the sleeves924 removed, the nasal insertion prongs 902 and 904 may each furthercomprise a lead 916 comprising a conductive loop 918. The conductiveloop 918 may comprise any suitable material or materials as describedherein. In some variations, the conductive loop 918 may compriseNitinol. In some variations, the conductive loop 918 may comprise acoating, which may enhance its electrochemical properties. The coatingmay comprise, for example, platinum or gold. The conductive loops 918may each be formed by crimping together two ends of a wire with crimptubes 920. The crimp tubes 920 may be welded to posts 922, which may beconfigured to be attached to the base member 906. The posts 922 maycomprise any suitable conductive material or materials as describedherein. In some variations the posts 922 may comprise stainless steel.Leads comprising conductive loops, such as conductive loops 918, may bedesirable in combination with sleeves that are removable (as describedbelow), since loops may be less likely to injure a user than a singlewire. In yet other variations, however, the stimulator probes describedhere may comprise leads comprising a single metal post, as shown inFIGS. 10A-10C and described in more detail below.

The leads 916 may be attached to the base member 906 in any suitablemanner. As shown in the exploded view of FIG. 9B, the posts 922 of theleads 916 may be held within first 938 and second 940 plates of the basemember 906. An assembled view of the stimulator probe 900 without thefirst plate 938 of the base member 906 is shown in FIG. 9C. Thestimulator probe 900 may further comprise contact springs 942, which maybe attached to the posts 922 (e.g., via laser welding). The contactsprings 942 may be formed from any suitable conductive material ormaterials as described herein, and may be configured to electricallyconnect the leads 916 to the circuitry of the stimulator body. Forexample, the contact springs may comprise a flexible region 946 that isconfigured to contact a portion of cable connectors 944 of a stimulatorbody (not shown) when the cable connectors 944 are reversibly insertedinto the base member 906 of the stimulator probe 900, as shown in FIG.9C.

The exterior of the nasal insertion prongs 902 and 904 may be formed bysleeves 924 covering the leads 916 of stimulator probe 900. The sleeves924 may comprise any suitable material or materials, which may desirablybe biocompatible, flexible, injection-moldable, and/or non-conductive.For example, the sleeves 924 may comprise a thermoplastic elastomer(e.g., a thermoplastic elastomer alloy (e.g., Versaflex™), thermoplasticpolyurethane, or the like), silicone, or the like. As shown in FIG. 9D,the sleeves 924 may comprise a distal portion 926, an elongate middleportion 928, and a base 930. As shown in the cut-away view of FIG. 9Eand cross-sectional view of FIG. 9F, the sleeves 924 may furthercomprise a central lumen 948, which may be configured to receive a lead916. The distal portion 926 and/or base 930 may have a larger diameter(or largest cross-sectional dimension) that is greater than the elongatemiddle portion 928, similar to the nasal insertion prongs 106 and 108described with respect to stimulator 100. This may allow a portion ofthe distal portions 926 (e.g., the electrodes, described below) to bebrought into contact with a subject's tissue, while the elongateportions 928 are not in contact with the subject's tissue.

Like the nasal insertion prongs 106 and 108 of stimulator probe 102, thenasal insertion prongs 902 and 904 may have any suitable distancebetween them, including all of the distances described with respect tothe prongs of stimulator probe 102. Nasal insertion prongs 902 and 904may also have any suitable length, including all of the distancesdescribed with respect to the prongs of stimulator probe 102. Similarly,the nasal insertion prongs 902 and 904 may have a particular flexibilityor range of flexibilities in order to allow the nasal insertion prongsto self-align to the desired stimulation location when inserted into auser's nasal cavities, as described with respect to the prongs ofstimulator probe 102.

The distal portions 926 of sleeves 924 may each comprise an opening 932,and the electrode 914 may be formed within the opening 932 of the distalportion 926. As described with respect to electrodes 110 and 112 ofstimulator 100, the electrodes 914 may comprise a portion of thecylindrical surface. As shown in the cross-sectional view of the sleeve924 in FIG. 9F, the electrodes 914 may comprise about a 100 degree arcof a cylindrical surface, but it should be appreciated that theelectrode may have any suitable size or shape, as described in moredetail with respect to electrodes 110 and 112 of stimulator probe 102.Like the electrodes 110 and 112 of stimulator probe 102 and described inmore detail, the electrodes 914 may be angled relative to the axisintersecting the first and second prongs, such that the electrodes maybe directed at least partially toward the front of the nose, which mayallow for selective activation of the nerves in the front of the nasalseptum. The electrodes 914 may be formed by a hydrogel located withinthe openings 932, and may comprise any suitable material, including ahydrogel. Like the electrodes 110 and 112 of stimulator probe 102, invariations in which the electrode 914 comprises a hydrogel, the hydrogelmay be any suitable hydrogel, including the hydrogels described in U.S.Provisional Patent Application No. 61/944,340, filed on Feb. 25, 2014,and titled “Polymer Formulations for Nasolacrimal Stimulation,” thecontents of which were previously incorporated by reference in theirentirety. Similarly, in some variations the distal portions 926 of thesleeves 924 may further be covered by a thin hydrogel skin. In somevariations, the sleeves 924 may comprise a retention column 952 locatedbetween the surface of the electrode and the central lumen 948. Theretention column 952 may help to retain the lead within the centrallumen 948 of the sleeve 924, and when the electrode 914 comprises ahydrogel, may help to retain the hydrogel within the opening 932.

The base 930 of the sleeves 924 may comprise a notch 936 configured toalign with a rod 934 on the base member 906 of the stimulator probe 900.The sleeves 924 may be reversibly removable from the stimulator probe900. In some variations, the sleeves 924 may be disposable, while theremainder of the stimulator probe 900 is reusable. The rod 934 and notch936 may assist the user in properly aligning the sleeve 924 with thebase member 906. In combination with an indicator on the stimulatorprobe 906 of the direction in which to hold the probe when inserting itinto the nose (e.g., a thumb groove 954), the proper alignment of thesleeves 924 with the base member 924 may be desirable in order to orientthe electrodes 914 toward the front of the nose when inserted, for thereasons described in more detail herein.

Insulation

Generally, when the stimulator probes described here are configured todelivery an electrical stimulus, the external surfaces of the any of thestimulator probes described herein may be insulated, with the exceptionof the electrodes. This may help to prevent inadvertent stimulation ofother tissue (e.g., by direct tissue contact with a lead instead of withan electrode). Accordingly, in some variations, the prongs may be formedfrom or otherwise coated with one or more insulating materials (e.g.,PTFE, silicone, combinations thereof, or the like). For example, in thevariation of the stimulator probe shown in FIGS. 6A-6F, the first andsecond prongs may be formed from an insulating material such as aflexible polymer (e.g., a thermoplastic elastomer (e.g., thermoplasticelastomer alloys (e.g., Versaflex™), thermoplastic polyurethanes, or thelike), silicone, or the like), and the leads may be positioned insidethe prongs such that they are electrically insulated from the exteriorsurfaces of the first and second prongs during use of the stimulatorprobe, as described herein. Accordingly, in these instances, electricalstimulation energy provided to the leads may be delivered via theelectrodes. Similarly, the material of sleeves 924 of stimulator probe900, and the sleeves 1024 of stimulator probe 1000, may be insulating.

Other Stimulator Probe Designs

The stimulator probes for use with the stimulators here may have anysuitable design. For example, FIGS. 11A-11B show another variation of astimulator probe 1100. In the variation shown there, the first 1101 andsecond 1103 nasal stimulation prongs may be formed from an insulatingmaterial such as silicone, and the leads 1118 may be positioned insidethe nasal stimulation prongs such that they are electrically insulatedfrom the exterior surfaces of the first 1101 and second 1103 nasalstimulation prongs during use of the stimulator probe 1100. Accordingly,in these instances, stimulation energy provided to the leads 1118 may bedelivered via the electrodes 1108.

The stimulator probe 1100 may be constructed in any suitable manner.FIG. 11B shows one example of a manner in which the stimulation probe1100 of FIG. 11A may be constructed. As shown there, the first 1101 andsecond nasal stimulation prongs 1103 may each be formed from a firstpiece 1120 and a second piece 1102, which each may be formed from one ormore insulating materials, such as described in more detail herein. Insome variations, the first piece 1120 and second piece 1102 may beformed as separate pieces. In other variations, such as shown in FIG.11B, the first piece 1120 and second piece 1102 may be formed with aliving hinge 1104 connecting the first piece 1120 and second piece 1102,such that the first 1120 and second 1102 pieces may be folded at theliving hinge 1104 to bring the first 1120 and second 1102 piecestogether. In some variations, the first 1120 and/or second 1102 piecesmay comprise one or more pegs 1106. These pegs 1106 may help to hold thefirst piece 1120 relative to the second piece 1102. Additionally, insome variations the leads 1118 may comprise one or more apertures 1107extending therethrough. In these variations, a lead 1118 may bepositioned between first 1120 and second 1102 pieces such that the pegs1106 extend through the apertures 1107 in the leads 1118. This may, inturn, control and maintain the position of a lead 1118 relative to thefirst 1120 and second 1102 pieces as well as a respective electrode1108.

The first piece 1120 may comprise a semi-cylindrical segment 1110configured to receive the electrode 1108. As shown in FIG. 11B, theelectrode 1108 may be formed as a hydrogel sheet 1112 on a backing layer1114. The hydrogel sheet 1112 may be wrapped around the semi-cylindricalsegment 1110, which may cause the hydrogel sheet 1112 to take on asemi-cylindrical shape. When the second piece 1102 is connected to thefirst piece 1120 to enclose the lead 1118, the hydrogel sheet 1112 maybe locked into place. For example, in some variations, the lead 1118 maycomprise one or more teeth 1116 or other projections extending from asurface of the lead 1118. When the first piece 1120 and second piece1102 are connected to enclose the lead 1110, the teeth 1116 or otherprojections may press into the hydrogel sheet 1112. This engagementbetween the teeth 1116 and the hydrogel sheet 1112 may mechanically holdthe hydrogel sheet 1112 in place as well as provide an electricalconnection between the lead 1118 and the electrode 1108. Stimulatorprobe 1200 shown in FIGS. 12A-12C may have similar features and may beconstructed in a similar manner as stimulator probe 1100, but may haveelectrodes 1208 angled toward each other, as described in more detailherein.

FIGS. 13A and 13B show perspective and cut-away perspective views,respectively, of another variation of a stimulator probe 1300 suitablefor use with the stimulators described here. As shown there, thestimulator probe 1300 may comprise first 1302 and second 1304 nasalstimulation prongs connected by a base member 1306, although it shouldbe appreciated that the stimulator probe 1300 may be configured with anysuitable number of nasal stimulation prongs as discussed below. Thefirst 1302 and second 1304 nasal stimulation prongs may be formed fromor covered with an insulating material or materials, such as discussedhere, and may each additionally comprise a lumen 1311 extending at leastpartially through each nasal stimulation prong. Each nasal stimulationprong may further comprise an electrode region 1308 comprising aplurality of apertures 1309 extending through the prong from an exteriorsurface of the prong to the lumen 1311. A conductive lead 1310 may bepositioned at least partially inside of each lumen 1311, and theapertures 1309 may facilitate an electrical connection between the leads1310 and tissue. For example, in some variations an electricallyconductive gel or solution (e.g., a hydrogel, saline) may be positionedinside of the apertures 1309 to provide a conductive pathway between thelead 1310 and tissue positioned externally of the prong, therebyallowing the electrode region 1308 to provide stimulation to tissue.While the stimulator probe 1300 is described here as configured todelivery an electrical stimulus, it should be appreciated that theplurality of apertures 1309 may also be configured to deliver otherforms of stimuli (e.g., chemical stimuli), as described in more detailbelow.

In some variations, the stimulator probes described here may beconfigured to adjust the distance between at least a portion of thefirst and second nasal insertion prongs. It may in some instances bedesirable to adjust the distance between at least a portion of the firstand second nasal insertion prongs (e.g., the electrodes) in order toaccommodate different nose sizes, achieve better contact between aportion of the nasal insertion prongs and the nasal tissue, hold thenasal insertion prongs in place, or the like.

In some of the variations in which the stimulator probe is configured toadjust the distance between at least a portion of the first and secondnasal insertion prongs, the stimulator probe may be configured to adjustthe angle between the first and second prongs. For example, FIG. 14shows a variation of a stimulator probe 1400 suitable for use with thestimulators described here. As shown there, the stimulator probe 1400may comprise first 1402 and second 1404 nasal insertion prongs connectedto a base member 1406. The base member 1406 may be configured to rotatethe first nasal insertion prong 1402 relative to the second nasalinsertion prong 1404. The base member 1406 may comprise a first grip1408, a second grip 1410, and a connector 1412 connecting the first grip1408 and the second grip 1410. Generally, the connector 1412 may beconfigured to act as a pivot point or flexible hinge to allow the firstgrip 1408 to rotate relative toward the second grip 1410. For example,in the variation of the stimulator probe 1400 shown in FIG. 14, theconnector 1412 may comprise a strip of resilient material that may bendor otherwise deflect when the first grip 1408 is pushed toward thesecond grip 1410. In other variations, the connector may comprise ahinge rotatably connecting the first grip and the second grip. As thefirst grip 1408 rotates toward the second grip 1410 (via the connector1412), the first prong 1402 may be configured to rotate away from thesecond prong 1404, which may increase the distance between the distalends of the first 1402 and second 1404 nasal insertion prongs.

In some of these variations, the first grip and second grip may bebiased toward a specific orientation, such that the base member returnstoward the predetermined orientation when forces on the base member areremoved. For example, the first 1402 and second 1404 nasal insertionprongs of stimulator probe 1400 may be connected to the base member 1406such that each of the first 1402 and second 1404 nasal insertion prongsare biased at an angle toward each other, as shown in FIG. 14. As shownthere, the nasal insertion prongs may be biased toward a configurationin which the distal ends of the first 1402 and second 1404 prongs areseparated by an initial distance (e.g., between about 3 mm and about 15mm). The first grip 1408 and second grip 1410 may be pressed toward eachother to rotate the first 1402 and second 1404 nasal insertion prongsaway from each other, which may increase the distance between the first1402 and second 1404 prongs. As the first 1408 and second grips 1410 arereleased, the return bias may cause the first grip 1408 and second group1410 to rotate away from each other, which may in turn return the distalends of the first 1402 and second 1404 prongs to their initialseparation distance.

When the first 1402 and second 1404 prongs are inserted into respectivefirst and second nasal cavities to position nasal tissue (e.g., a nasalseptum) between the prongs (as will be discussed in more detail below),the first 1402 and second 1404 prongs may be rotated away from eachother prior to insertion into the respective nasal cavities. Oncepositioned in the nasal cavities, the force applied to the first 1408and second 1410 grips may be released and the return bias may rotate thefirst 1402 and second 1404 prongs toward each other. If the initialseparation distance between the first 1402 and second 1404 prongs isless than the width of the nasal tissue positioned between the prongs,the return bias of the stimulator probe 1400 may press the distal endsof the first 1402 and second 1404 prongs against tissue. This may helpto increase electrode apposition with tissue, and in some instances mayact to hold the stimulator probe 1400 in place relative to tissue. Toremove the stimulator probe 1400 from tissue, the first 1402 and second1404 prongs may again be rotated away from each other to release thetissue positioned between the prongs.

When the distal ends of the first 1402 and second 1404 nasal insertionprongs comprise electrodes 1414 and 1415, changing the distance betweenthe distal ends of the nasal insertion prongs may correspondingly changethe distance between the electrodes 1414 and 1415. As describedelsewhere herein, the electrodes 1414 and 1415 of stimulator probe 1400may comprise one or more conductive materials, may have a relativelyatraumatic shape (e.g., a spherical shape, and may comprise one or morefoam covers 1418.

FIGS. 10A, 10B, and 10C show perspective, back cut-away, and side views,respectively, of another stimulator probe configured to adjust the anglebetween first and second nasal insertion prongs. As shown there, thestimulator probe 1000 may comprise first 1002 and second 1004 nasalinsertion prongs connected to a base member 1006. The base member 1006may be configured to rotate the first nasal insertion prong 1002relative to the nasal insertion second prong 1004. The base member 1006may comprise a first grip 1008, a second grip 1010, and a connector 1012connecting the first grip 1008 and the second grip 1010. Like connector1412 of stimulator probe 1400, the connector 1012 may be configured toact as a pivot point or flexible hinge to allow the first grip 1008 torotate relative toward the second grip 1010. The connector 1012 maycomprise a strip of resilient material that may bend or otherwisedeflect when the first grip 1008 is pushed toward the second grip 1010.As the first grip 1008 rotates toward the second grip 1010 (via theconnector 1012), the first prong 1002 may be configured to rotate awayfrom the second prong 1004, which may increase the distance between thedistal ends of the first 1002 and second 1004 prongs.

The first 1002 and second 1004 nasal insertion prongs may be connectedto the base member 1006 such that each of the first 1002 and second 1004nasal insertion prongs are biased at an angle toward each other, asshown in FIGS. 10A-10C, such that the distal ends of the first 1002 andsecond 1004 prongs are separated by an initial distance (e.g., betweenabout 1 mm and about 20 mm, between about 5 mm and about 10 mm, betweenabout 10 mm and about 15 mm, about 12 mm). The first grip 1008 andsecond grip 1010 may be pressed toward each other to rotate the first1002 and second 1004 nasal insertion prongs away from each other, whichmay increase the distance between the first 1002 and second 1004 nasalinsertion prongs. As the first 1008 and second grips 1010 are released,the return bias may cause the first grip 1008 and second group 1010 torotate away from each other, which may in turn return the distal ends ofthe first 1002 and second 1004 prongs to their initial separationdistance.

When the first 1002 and second 1004 prongs are inserted into respectivefirst and second nasal cavities to position nasal tissue (e.g., a nasalseptum) between the prongs (as will be discussed in more detail below),the first 1002 and second 1004 nasal insertion prongs may be rotatedaway from each other prior to insertion into the respective nasalcavities. Once positioned in the nasal cavities, the force applied tothe first 1008 and second 1010 grips may be released and the return biasmay rotate the first 1002 and second 1004 nasal insertion prongs towardeach other. If the initial separation distance between the first 1002and second 1004 nasal insertion prongs is less than the width of thenasal tissue positioned between the prongs, the return bias of thestimulator probe 1000 may press the distal ends of the first 1002 andsecond 1004 nasal insertion prongs against tissue. This may help toincrease electrode apposition with tissue in variations in which theprobes comprise electrodes, and in some instances may act to hold thestimulator probe 1000 in place relative to tissue. To remove thestimulator probe 1000 from tissue, the first 1002 and second 1004 prongsmay again be rotated away from each other to release the tissuepositioned between the prongs. When the distal portions of the first1002 and second 1004 nasal insertion prongs comprise electrodes 1014 and1015, as described below, changing the distance between the distal endsof the nasal insertion prongs may correspondingly change the distancebetween the electrodes 1014 and 1015.

In some variations, the stimulator may comprise a buzzer. The buzzer maycreate a buzzing noise when stimulus is being delivered by thestimulator probe, which may provide feedback to the user that thestimulator is working. For example, stimulator probe 1000 may comprise abuzzer 1016. As shown in FIG. 10A, the buzzer 1016 may be located on thebase member 1006 between the first 1008 and second 1010 grips in a waythat still allows the prongs to be rotated relative to each other. Insome instances, the buzzer 1016 may be attached to the first grip 1008.Additionally or alternatively, the base member 1006 may comprise otherelectrical components (e.g., a controller, memory, or the like).

The first 1002 and second 1004 nasal insertion prongs may each compriseleads comprising a metal post 1018, which may be covered by sleeves1024. The metal posts 1018 may comprise any suitable conductive materialor materials (e.g., stainless steel, titanium, titanium nitride,platinum, alloys thereof or the like). The sleeves may have the sameproperties as described with respect to sleeves 924. As described inmore detail with respect to sleeves 924, the sleeves 1024 may compriseany suitable material or materials, which may desirably bebiocompatible, flexible, injection-moldable, and/or non-conductive. Forexample, the sleeves 1024 may comprise a thermoplastic elastomer (e.g.,a thermoplastic elastomer alloy (e.g., Versaflex™), thermoplasticpolyurethane, or the like), silicone, or the like. The sleeves 1024 maycomprise a distal portion 1026, an elongate middle portion 1028, and abase 1030. The distal portion 1026 and/or base 1030 may have a largerdiameter (or largest cross-sectional dimension) that is greater than theelongate middle portion 1028, similar to the nasal insertion prongs 106and 108 described with respect to stimulator 100. The distal portion1026 may comprise an opening 1032, and the electrode 1014 may be formedby a hydrogel located within the opening 1032 of the distal portion1026. The electrodes 1014 may comprise a portion of the cylindricalsurface. The base 1030 of the sleeves 1024 may comprise a notch 1036configured to align with a rod 1034 on the base member 1006 of thestimulator probe 1000. The sleeves 1024 may be reversibly removable fromthe stimulator probe 1000. In some variations, the sleeves 1024 may bedisposable, while the remainder of the stimulator probe 1000 mayreusable.

In some of the variations in which the stimulator probe is configured toadjust the distance between at least a portion of the first and secondnasal insertion prongs, the stimulator may be configured such that thedistance between the two nasal insertion prongs is adjustable,independent of adjusting the angle between the two nasal insertionprongs. For example, in variations in which the nasal insertion prongsare connected by a base member, one or more of the nasal insertionprongs may be capable of sliding relative to the base member.Additionally or alternatively, the base member may be adjustable in size(e.g., may comprise two pieces, each comprising a nasal insertion prong,that are configured to slide apart or together) to alter the spacingbetween the prongs.

While the nasal insertion prongs described herein may be connected via abase member, it should be appreciated that in other variations, eachprong may be individually connected to the stimulator body, which mayallow the prongs to be individually disconnected and/or replaced. Thus,in other variations where a stimulator comprises two or more nasalinsertion prongs, the prongs may not be connected to each other. Invariations where individual nasal insertion prongs are directlyconnected to a stimulator body, the connection between the nasalinsertion prongs and the stimulator body may control the relativepositioning of the nasal insertion prongs. It should also be appreciatedthat in some variations where the stimulator probe includes a basemember or other structure connecting two or more nasal insertion prongs,the stimulator probe may be configured such that individual prongs maybe disconnected from the stimulator probe and replaced.

While the stimulator probes are described in some instances herein withrespect to delivery of an electrical stimulus, it should be appreciatedthat the stimulators described here may be configured to deliver othertypes of stimuli, including mechanical, chemical, or other forms ofstimulation. In variations in which the stimulators are configured todeliver a mechanical stimulus, the nasal insertion prongs may beconfigured to deliver vibrational energy to nasal tissue. In variationswhere a stimulator comprises one or more prongs configured to beinserted at least partially into a nasal cavity (such as describedherein), the prongs may be configured to vibrate relative to tissue. Invariations where a stimulator is implanted in a nasal or sinus cavity,one or more portions of the stimulator may be configured to vibrate. Insome of these variations, the vibration may be generated using one ormore magnets positioned externally of the body. In these variations,mechanical energy may be used to activate mechanical receptors inafferent neurons.

Additionally or alternatively, the nasal insertion prongs may beconfigured to deliver ultrasonic energy to tissue. In these variations,the nasal insertion prongs (and stimulator bodies) may be configured tohave similar physical properties as described herein, although the nasalinsertion prongs need not comprise electrodes. Instead, the nasalinsertion prongs or the stimulator body may comprise vibrating motors invariations configured to vibrate all or a portion of the nasal insertionprongs, or may comprise one or more ultrasound transducers configured todeliver ultrasonic energy. In some variations, the ultrasoundtransducers may be located in place of the electrodes described herein.

In some other variations, the stimulators described here may beconfigured to deliver thermal, light-based, and/or magnetic stimuli. Insome variations, stimulators may be configured to deliver one or morepulses of air to tissue via the nasal insertion prongs, which maystimulate tissue. The pulses of air may be generated via a source ofcompressed air, or the like. In some variations, the gas may be warmedor cooled (e.g., mechanically or via one or more thermally-activatedfibers). In other variations, the nasal insertion prongs may be heatedor cooled to provide thermal stimulation to tissue. Additionally oralternatively, the stimulator may comprise one or more light-generatingor magnetic field-generating elements, which may be used to stimulatenasal or sinus tissue via the nasal insertion prongs.

In yet other variations, the stimulator probes may be configured todeliver one or more chemical agents to nasal tissue. The chemical agentmay be one or more drugs, such as a histamine receptor agonist,nicotinic agonist, or the like. In other variations, the chemical agentmay contain one or more irritants, such as ammonia, benzene, nitrousoxide, capsaicin (e.g., propanethial S-oxide), mustard oil, horseradish,crystalline silica, or the like. The nasal insertion prongs may in theseinstances comprise delivery ports for delivering one or more chemicalagents, and may additionally comprise lumens connecting the deliveryports to one or more reservoirs located in the base member of thestimulation probe and/or in the stimulator body.

For example, FIGS. 35A-35B depict cut-away views of a handheldstimulator 3500 configured to deliver one or more chemical agents. Asshown there, the stimulator 3500 may comprise a stimulator body 3502 anda stimulator probe 3504, which may be permanently or detachablyconnected. The stimulator body 3502 may comprise a reservoir 3506configured to hold one or more chemical agents. The chemical agents maybe held in any suitable form. The stimulator probe 3504 may comprise oneor more nasal insertion prongs (here, two nasal insertion prongs 3508and 3510). The reservoir 3506 may be connected via lumens 3512 and 3514to delivery ports 3516 and 3518 located on the nasal insertion prongs3508 and 3510. The user may be able to cause delivery of the one or morechemical agents using an operating mechanism (e.g., button 3520 on thestimulator body 3502). In some variations, such as shown in FIGS.35A-35B, the applying pressure to the button 3520 may cause the button3520 to press on the reservoir 3506, causing the one or more chemicalagents to flow through the lumens 3514 and 3514 and out the deliveryports 3516 and 3518. The chemical agents may be in any suitable vehicle(e.g., liquid, aerosol, gas, etc.). However, it should be appreciatedthat in other variations, stimulators configured to deliver one or morechemical agents may comprise an automated delivery mechanism, such asone or more pumps connected to internal circuitry and/or intelligence.In some instances, these stimulators may be configured to deliverelectrical stimulation (such as described herein) to nasal or sinustissue to promote or otherwise facilitate the uptake of one or morechemical agents by the tissue (e.g., by iontophoresis).

While the stimulator probes in the figures described herein are shown ashaving two nasal stimulation prongs, it should be appreciated that inother variations the stimulator probe may have any suitable number ofprongs (e.g., one, two, or three or more prongs). For example, in somevariations where the stimulator is configured for monopolar stimulation,the stimulator probe may comprise a single nasal insertion prong.Similarly, the stimulators may comprise any suitable number ofelectrodes (e.g., one, two, three, or four or more electrodes), and theelectrodes may be positioned on any suitable portion of the stimulator(e.g., the stimulator body and/or a stimulator probe). In somevariations where a stimulator comprises two prongs (such as described inmore detail herein), a first prong may comprise an electrode while thesecond prong may not include an electrode. These variations may findparticular utility in instances where the stimulator is configured todeliver monopolar stimulation (or unilateral stimulation of a singlenostril). In these variations, the non-electrode bearing nasal insertionprong may be configured to help hold tissue between the two prongs (asdescribed in more detail herein), or may be configured to delivernon-electrical energy from the prong (e.g., vibratory energy, thermalenergy, or the like, as discussed in more detail herein).

Connection Between Stimulator Body & Probe

Physical Connection

The stimulator probes described here (and any prongs thereof) may beconnected to a stimulator body in any suitable manner. In somevariations, a stimulator probe may be configured to directly connect toa stimulator body. In these variations, at least a portion of thestimulator probe may have a fixed location and orientation with respectto the stimulator body when the two are connected. In some of thesevariations, the stimulator probe may be permanently connected to thestimulator body. For example, the stimulator probe and stimulator bodymay be formed together such that they are permanently connected. Inother variations, the stimulator probe may clip, latch, snap onto, orotherwise mechanically connect to the stimulator body. In some of thesevariations, the stimulator probe may be releasably connected to thestimulator body, such that the stimulator probe may be disconnected fromthe stimulator body after being connected.

For example, stimulator body 102 and stimulator probe 104 of stimulator100 may be removably connected such that a portion of the stimulatorprobe 104 directly contacts and connects to the stimulator body 104.FIG. 15A depicts a perspective view of the stimulator 100 showing theconnection mechanism. As shown there, the distal portion 206 of the tophousing 142 of the stimulator body 102 and the proximal portion of thestimulator probe 104 may comprise corresponding and complementaryshapes, which may allow the stimulator body 102 and stimulator probe 104to be attached. For example, the distal portion 206 of the top housing142 of the stimulator body and the proximal surface of the rigid support218 of the stimulator probe 104 may comprise features that allow them tobe reversibly attached. For example, in the variation shown the distalportion 206 of the top housing 142 of the stimulator body 102 maycomprise two notches 192 on a first side and two notches 194 on a secondside. The proximal surface of the rigid support 218 of stimulator probe104 may comprise four corresponding tabs: two tabs 196 on a first sideand two tabs 198 on a second side (shown in FIG. 6E). The stimulatorbody 102 and stimulator probe 104 may be snapped together by firstplacing tabs 198 of the stimulator probe 104 into the notches 194 ofstimulator body 102, and then manipulating the probe 104 and body 102such that the first side of the simulator body 102 is rotated toward thefirst side of the stimulator probe 104. In doing so, the tabs 196 of thestimulator probe 104 may be rotatably inserted into the notches 192 ofthe stimulator body 102. The tabs 196 and 198 and notches 192 and 194may have increased height and depth, respectively, at their proximalends, such that the probe 104 and body 102 are held together by the tabsand notches when connected.

Conversely, the stimulator probe 104 may be removed from the stimulatorbody 102 by rotating the first side of the probe 104 and first side ofthe body 102 away from each other. It may be desirable for thestimulator to be configured such that when a user inserts the stimulatorprobe 104 into his/her nasal cavities, if the user presses a portion ofthe stimulator prongs (e.g., the electrodes) against tissue (e.g.,tissue near the front of the nose), the force on the stimulator probereinforces the connection between the stimulator probe 104 and thestimulator body 102. That is, the force from the user's tissue maydesirably tend to push the first side of the stimulator body 102 towardthe first side of the stimulator probe 104. If, instead, the forcetended to push the first side of the probe 104 and the first side of thebody 102 away from each other, there could be an increased risk of theprobe being inadvertently disconnected from the stimulator body duringstimulation. In some variations, as described in more detail below, thestimulator probe 104 may further comprise tab 200 configured to fit intonotch 202 of stimulator body 102, which may help the control subsystem136 to register the connection of the stimulator probe 104 to thestimulator body 102.

It should be appreciated that in other variations, the stimulator bodyand stimulator probe may have any suitable features for being attached,such as other snapping mechanisms (e.g., having different shapes ordifferent numbers of features), magnets, friction fits, a latchingmechanism, or the like. For example, in some variations the stimulatorbody may comprise a magnet (e.g., magnet 134 of stimulator body 102)connected to the interior surface of the proximal housing of thestimulator body, as described in more detail herein. The stimulatorprobe may comprise a magnet or ferromagnetic material in a correspondinglocation (e.g., in the base member of the stimulator probe), which mayretain the stimulator probe on the stimulator body.

In some variations where the stimulator body is releasably connected tothe stimulator probe, the stimulator may comprise a release mechanism,although the stimulator need not comprise a release mechanism. In somevariations, the release mechanism may comprise a button, switch, lever,or the like, which may be activated to disconnect the stimulator probefrom the stimulator body. In other variations, the release mechanism maybe controlled by the control subsystem. Example of release mechanismsare shown in FIGS. 16A and 16B. In the stimulator 1600 of FIG. 16A, thestimulator probe 1604 may be configured to releasably connect tostimulator body 1602. The stimulator body 1602 may comprise a releasemechanism 1606, which may decouple the stimulator probe 1604 from thestimulator body 1602. The release mechanism 1606 may be manuallymanipulated by the user and may comprise a sliding button; as the buttonis moved from the position shown in FIG. 16A to a distal position, thestimulator probe 1604 may be released. Similarly, in the stimulator 1650of FIG. 16B, the stimulator probe 1654 may be configured to releasablyconnect to stimulator body 1652. The stimulator body 1652 may comprise arelease mechanism 1656, which may decouple the stimulator probe 1654from the stimulator body 1652. The release mechanism 1656 may bemanually manipulated by the user. In some variations, the releasemechanism 1656 may comprise a sliding button; as the button is movedfrom the position shown in FIG. 16B to a distal position, the stimulatorprobe 1654 may be released. In some variations, the release mechanism1656 may comprise a push button; as the button is pushed inward, thestimulator probe 1654 may be released. In some variations, the releasemechanism 1656 may release the stimulator probe 1654 by moving a portionof an attachment mechanism (e.g., a tab, hook, or the like). In somevariations comprising a release mechanism, the release mechanism maycomprise a seal to waterproof any openings.

In other variations, the stimulator probe and the stimulator body may beindirectly connected via a cable, cord, or the like. In thesevariations, the stimulator probe and stimulator body may be movablerelative to each other while they are connected. For example, in thevariation of the stimulator probe 1400 shown in FIG. 14, the stimulatorprobe 1400 may be configured to connect to a stimulator body (not shown)via one or more cable connectors 1416. In the variation shown in FIG.14, the cable connectors 1416 may be releasably connected to thestimulator probe 1400. In these variations, the cable connectors 1416may be permanently or releasably connected to the stimulator body. Inother variations, the cable connectors 1416 may be permanently connectedto the stimulator probe 1400. In these variations, the cable connectors1416 may be releasably connected to the stimulator body (e.g., to allowthe stimulator probe 1400 to be releasably connected to the stimulatorbody) or permanently connected to the stimulator body (e.g., to allowthe stimulator probe 1400 to be permanently connected to the stimulatorbody). The stimulator probes 900 and 1000 in FIGS. 9A-9F and 10A-10C,respectively, may similarly be indirectly connected via a cable, cord,or the like to a stimulator body, such as via cable connectors 944 and1044, respectively.

Electrical Connection

Generally, when the stimulators described here are configured to deliveran electrical stimulus, the electrodes of the stimulator may beelectrically connected to the stimulator circuitry, such that thestimulator may generate a stimulus and deliver it to tissue via one ormore of the electrodes. Accordingly, the stimulators described here maycomprise one or more electrical connections configured to electricallyconnect the electrode via a lead to a portion of the stimulator body(e.g., a stimulation subsystem housed in the stimulator body). Invariations in which the stimulator probe and stimulator body areindirectly connected, the indirect connection (e.g., a cable, cord, orthe like) may serve as the electrical connection between the stimulatorcircuitry and the electrodes. In variations in which the stimulatorprobe and the stimulator body are directly connected, the stimulatorbody and stimulator probe may comprise conductive elements configured toelectrically connect the electrodes of the stimulator probe to thestimulator circuitry when the body and probe are connected.

For example, as shown in FIG. 1D, the electrodes 110 and 112 ofstimulator probe 104 may be connected to leads 130 and 132 locatedwithin nasal insertion prongs 106 and 108, respectively. Thecorresponding stimulator body 102 may comprise connectors 122 and 124directly or indirectly connected to the control subsystem 136 and powersource 152. The distal ends of the connectors 122 and 124 may beconfigured to connect with the proximal ends of the leads 130 and 132 ofthe stimulator probe 104. As shown in FIG. 3A, in some variations thedistal ends of the connectors may comprise a rounded surface. Asdescribed above, in variations in which the leads comprise springs, theproximal ends of the springs may have a tighter pitch than the rest ofthe springs. This may create a more even surface to contact proximalends of the connectors, and thus may allow for a better electricalconnection between the leads of the stimulator probe 104 and theconnectors of the stimulator body 102.

When the proximal ends of the springs of stimulator probe 104 are incontact with the connectors 122 and 124 of the stimulator body 102, thesprings may be compressed. This compression may cause the springs togenerating a restoring force. The restoring force may promote contactbetween the springs and the connectors 122 and 124. However, invariations in which the stimulator probe 104 is removably connectable tothe stimulator body 102, the restoring force may also act against theforce of the connection mechanism holding together the stimulator probeand the stimulator body (e.g., notches 192 and 194 and tabs 196 and198). Thus, it may be desirable for the spring stiffness to be lowenough that the restoring force of the springs does not cause thestimulator probe to disconnect from the stimulator body.

The connectors 122 and 124 may extend through lumens 208 and 210 in theproximal housing 142, and the proximal ends may be directly orindirectly attached to the control subsystem. As shown in FIG. 3D, theproximal ends of the connectors 122 and 124 may comprise slotsconfigured to receive the distal ends of contact strips 244. Theproximal ends of contact strips 244 may be attached to the controlsubsystem 136 (i.e., may be attached to the printed circuit board 128).The connectors and contact strips may comprise any suitable conductivematerial or materials, such as but not limited to stainless steel,titanium, copper, nickel, brass, zinc, or the like, which may in someinstances be gold-plated.

It should be appreciated that the stimulator body and stimulator probemay additionally or alternatively be inductively coupled, such thatpower may be transferred from the stimulator body to the stimulatorprobe via induction. In these variations, the stimulator body andstimulator probe may each comprise a coil. In some variations, each ofthe coils may be wrapped around a ferromagnetic (e.g., iron) core, butneed not be. In some variations, the coil of the stimulator body and/orstimulator probe may be a printed coil.

Disposable Design

In some variations, some or all of the stimulator may be disposable. Invariations where the stimulator body is permanently attached to thestimulator probe, the entire stimulator may be disposable. In othervariations, one or more portions of the stimulator may be reusable. Forexample, in variations where the stimulator probe is releasablyconnected to the stimulator body, the stimulator body may be reusable,and the stimulator probe may be disposable. As such, the stimulatorprobe may be periodically replaced, such as will be described in moredetail below. In yet other variations, a portion of the stimulator probemay be disposable (e.g., the stimulator probe may comprise disposablesleeves or disposable prongs) and may be periodically replaced. In somevariations, the stimulators described here may comprise features thatencourage or require a user to replace a stimulator or stimulatorcomponents after a certain period or on a regular basis in order to mainproper hygiene.

In variations in which the entire stimulator is disposable (e.g., whenthe stimulator probe is integrally formed with or permanently attachedto the stimulator body), the stimulator may be configured to becomenon-operational after a certain period of time and/or use. In some ofthese variations, the stimulator may be configured to limit the durationof stimulation that may be provided by the stimulator; after theduration limit, the stimulator may be configured to becomenon-operational. For example, the stimulator may have a power sourcethat is only sufficient to power stimulus delivery for a predeterminedduration (e.g., one hour of stimulation). Once the power source has beendepleted, a user may need to replace the spent stimulator with a newstimulator. In some of these variations, the stimulator may beconfigured such that the power source cannot be accessed withoutrendering the device inoperable, which may help prevent users fromreplacing the power source.

As another example, the stimulator additionally or alternatively may beprogrammed to limit the duration or amount of stimulus delivery with agiven stimulator. In some of these variations, the stimulator may beconfigured to measure and store the duration of stimulation provided bythe stimulator over time (which may be cumulatively added over aplurality of different treatment sessions). When the duration reaches athreshold limit (e.g., about 10 minutes, about 30 minutes, about onehour, about 2 hours, or longer than 2 hours), the stimulator may beprogrammed to switch to an inoperable state, whereby the stimulator maynot be activated to provide additional stimulation. As another example,the stimulator additionally or alternatively may be configured to limitthe number of treatment sessions provided by the stimulator. In some ofthese variations, the stimulator may be configured to measure and storethe number of treatment sessions provided by the stimulator. When thenumber of treatment sessions reaches a threshold limit (e.g., five uses,ten uses, fifteen uses, or more than fifteen uses), the stimulator maybe programmed to switch to an inoperable state, whereby the stimulatormay not be activated to provide additional stimulation.

In these or other variations in which the entire stimulator isdisposable, the stimulator may additionally or alternatively beconfigured to become non-operational after a certain period of timeafter its first use. The stimulator may be configured to limit theduration since the first use of the stimulator; after the durationlimit, the stimulator may be configured to become non-operational. Insome of these variations, the stimulator may be configured to store dateand time information regarding the first use of the stimulator. Thestimulator may be further configured to switch to an inoperable statewhen a predetermined amount of time (e.g., one day, two days, five days,one week, two weeks, or longer than two weeks) has passed from the firstuse of the stimulator.

In any of these variations, the stimulator may be configured to limitthe duration of stimulus delivery, the number of treatment sessions, orthe duration since first use via a control subsystem, which may in someinstances comprise intelligence such as a microcontroller, programmablelogic (e.g., a field-programmable gate array), or anapplication-specific integrated circuit (ASIC) configured to measure,store, and limit the duration and/or number of treatment sessions and/orthe time since first use of the stimulator. In any of these variations,when the device moves to an inoperable state, the user may need toreplace the inoperable stimulator with a new stimulator.

In variations in which the stimulator body is reusable and all or aportion of the stimulator probe is disposable, the stimulator may beconfigured to encourage and/or require the user to replace all or aportion of the stimulator probe. In some of these variations, thedisposable portion probe or portion of the probe may comprise arecyclable material. In some of these variations, the stimulator may beconfigured such that the stimulator probe or a portion thereof becomesinoperable after being attached to the stimulator body for apredetermined amount of time (e.g., between about 1 hour and about 24hours, between about 1 day and about 7 days, between about 1 week andabout 4 weeks, between about 1 month and about 3 months, or longer thanabout 3 months), after a predetermined number of treatment sessions,and/or after a predetermined duration of stimulation (e.g., betweenabout 2 minutes and about 30 minutes, between about 30 minutes and about1 hour, between about 1 hour and about 3 hours, between about 3 hoursand 12 hours, or longer than about 12 hours).

For example, in some variations of stimulators comprising one or moreelectrodes, the electrodes of the stimulator probe may become inoperableafter being attached to the stimulator body for a predetermined amountof time, after a predetermined number of treatment sessions, and/orafter a predetermined duration of stimulation. For example, in somevariations it may be desirable to promote oxidation of one or more ofthe electrodes during stimulation. In these variations, the electrodemay be configured to form a non-conductive (or reduced conductivity)layer on the surface of the electrode. In some variations, this mayinterfere with the ability of the electrode to stimulate tissue, andeventually the oxide layer may substantially prevent any electricalenergy from being supplied to the user. In some instances, to form sucha layer, the stimulator may be configured to deliver biphasic pulsesusing the electrodes, wherein the biphasic pulses are notcharge-balanced. By not charge-balancing the stimulation pulses, chargemay accumulate on one or more of the electrodes and/or leads, which mayfacilitate oxidation of the metal of the electrode and/or lead. The rateof the oxidation may be controlled at least partially by the materialsof the electrode and/or lead and the parameters of the pulses deliveredby stimulator, and the rate of oxidation may be tailored to achieve apredetermined treatment duration or number of treatment sessions beforeformation of an oxide layer may render the stimulator inoperable. Asanother example, in some variations, an electrode of a stimulator probeadditionally or alternatively may be configured to change color overtime (e.g., as a result of delivering stimulation, as a result of carbondioxide exposure, as a result of oxidation), such that a user may beprompted to change the stimulator probe when the electrode reaches acertain color. In these variations, the stimulator probe or a portion ofthe stimulator probe (e.g., nasal insertion prongs or sleeves comprisingthe electrodes) may be replaced when the electrodes of the stimulatorprobe are unable to provide stimulation or when the stimulatorencourages replacement via the color change.

As yet another example, in some variations the stimulator may beprogrammed to render the stimulator probe inoperable and/or to encouragereplacement of the stimulator probe or a portion thereof (e.g.,disposable prongs or sleeves) after being attached to the stimulatorbody for a predetermined amount of time, after a predetermined number oftreatment sessions, and/or after a predetermined duration ofstimulation. In some of these variations, the stimulator may beprogrammed to measure the duration of stimulation provided using aspecific stimulator probe or portion thereof, the number of treatmentsessions provided using a specific stimulator probe or portion thereof,and/or the duration of attachment of a specific stimulator probe orportion thereof to the stimulator, via mechanisms described in moredetail below. In variations where the stimulator is programmed tomeasure multiple of the above-listed parameters, if the measurementreaches a threshold value, the stimulator may be configured to alert theuser and/or to enter an inoperable state until the current stimulatorprobe or portion thereof is replaced. In variations where the stimulatoris programmed to measure multiple of the above-listed parameters, thestimulator may be configured to alert the user and/or enter theinoperable state when any of the measured parameters reaches itsthreshold value, or the stimulator may require multiple of the measuredparameters to reach their corresponding threshold values in order toalert the user and/or enter an inoperable state. The stimulator mayalert the user in any suitable manner, including visual feedback (e.g.,generating a prompt on a display, activating a LED, notifying the useron another device, such as a computer or mobile device, or the like),audio feedback (e.g., generating one or more beeps or audio prompts),and/or tactile feedback (e.g., vibrating the stimulator). Similarly, invariations in which the stimulator has entered its inoperable state, thestimulator may additionally or alternatively be configured to instructthe user to replace the stimulator probe. This may also be done in anysuitable manner, including visual, audio, or tactile feedback asdescribed above, and herein throughout.

An example of one mechanism for measuring how long a stimulator probe104 has been connected to the stimulator body 102 is shown in FIGS.15B-15C. The mechanism may comprise a detector connected to the memoryof the control subsystem, which may record how long the detector detectsthe stimulator probe. In some variations, the detector may comprise anLED or laser and a sensor (e.g., a photodiode) to detect the lightemitted by the LED or laser. The transmission of light to the sensor maybe blocked when the stimulator probe is connected to the stimulatorbody. FIGS. 15B-15C illustrate a sensor 172 configured to detect lightfrom an LED or laser (not shown). Movable rod 168 is shown in a firstposition in FIG. 15B, when the stimulator probe 104 has not yet be fullyconnected to stimulator body 102. The movable rod 168 may be biased by aspring 170 such that when the stimulator probe 104 is not connected tothe stimulator body 102, the movable rod 168 does not block thetransmission of light from the LED or laser to the sensor 172. When thestimulator probe 104 is attached to the stimulator body 102 (as shown inFIG. 15C), a portion of the stimulator probe (e.g., tab 200) may enternotch 202 of the stimulator body 102 and may press on the movable rod168, causing the moveable rod 168 to block the transmission of light tothe sensor 172. The sensor 172 may transmit this information to thecontrol subsystem 136, which may allow the stimulator 100 to measure theduration of attachment. When a predetermined attachment duration isreached, the probe 104 may be disabled, or the user may be encouraged toreplace the stimulator probe 104 in any of the manners described herein.The duration may be, for example, between about 1 hour and 24 hours,between about 1 day and 7 days, between 1 week and about 4 weeks,between about 1 month and 6 months, or longer than 6 months. Thestimulator may be configured to do so via intelligence in the controlsubsystem 136, such as a microcontroller, programmable logic (e.g., afield-programmable gate array), or an application-specific integratedcircuit (ASIC).

It should be appreciated that any suitable method may be used todetermine whether and for how long a stimulator probe is attached. Forexample, the stimulator body may be configured to measure thecapacitance across the connectors 122 and 124. As another example, thestimulator body may be configured to detect an RFID chip located in thestimulator probe. Based on the identifier associated with the RFID chip,the stimulator may also be configured to determine whether thestimulator probe is new. As yet another example, the stimulator body maycomprise two electrical connections that may be short circuited when thestimulator probe is attached. For example, the stimulator body maycomprise two conductive pads on the proximal housing 142, which may beelectrically connected via a foil strip on the proximal end of thestimulator probe when the stimulator probe is attached to the stimulatorbody. The control subsystem 136 may be configured to detect whether thetwo conductive pads are short circuited. As yet another example, thestimulator body may comprise a magnetic sensor (e.g., a Hall effectsensor) configured to detect a magnet that may be located in thestimulator probe. As yet another example, the stimulator body maycomprise a coil, while the probe may comprise a conductor (e.g., aconductive foil). The coil may be configured to inductively detect thepresence of the conductor in the stimulator probe when the probe isconnected to the stimulator body.

Additionally or alternatively, in some variations the stimulator may beconfigured to alert the user and/or enter an inoperable state when aused stimulator probe is attached to the stimulator body. The stimulatormay alert the user in any suitable manner, and may additionally oralternatively be configured to instruct the user to replace thestimulator probe, as described herein. In these variations, thestimulators may comprise a mechanism for determining whether theattached stimulator probe is new (i.e., whether the stimulator probe hasbeen previously attached to a stimulator body or not). In somevariations, the mechanism for determining whether the stimulator probeis new may comprise a fuse. In some variations, the fuse may temporarilyshort circuit the stimulator circuitry while the probe is beingconnected to the stimulator body.

In some variations, the fuse may be a mechanical fuse. FIGS. 17A-17Eshow one example of a stimulator 1700 comprising a stimulator body 1702and a stimulator probe 1704, and comprising mechanical fuse. Stimulatorprobe 1704 is shown as translucent in FIGS. 17A-17E for explanatorypurposes. The stimulator probe 1702 may comprise a thin conductive strip1706 (e.g., aluminum, metalized plastic, or the like), as shown in anexploded view in FIG. 17A. As shown in FIG. 17C, the conductive strip1706 may be attached to the proximal surface of the stimulator probe1704. The conductive strip 1706 may comprise an adhesive (e.g., contactglue) on its distal side in order to attach it to the proximal surfaceof the stimulator probe 1704. When attached to the stimulator probe1704, the conductive strip 1706 may cover openings 1708 in thestimulator probe 1704 through which the leads 1710 are configured tocontact the electrical connectors 1712 of the stimulator body 1702. Thedistal surface of the stimulator body 1702 may comprise a protrusion1714. The protrusion 1714 may have a sharp edge or point, and mayfurther comprise a non-conductive material (e.g., a plastic). As thestimulator probe 1704 is attached to the stimulator body 1702, theconductive strip 1706 of the stimulator probe 1704 may come into contactwith the two electrical connectors 1712 of the stimulator body 1702, asshown in FIG. 17D. The conductive strip 1706 may thus electricallyconnect the two electrical connectors 1712, causing a short circuitbetween the two connectors. As the stimulator probe 1704 is furtherpressed down and connected to the stimulator body 1702, as shown in FIG.17E, the protrusion may break the conductive strip 1706 into twoelectrically separate pieces. (The stimulator probe 1704 may comprise arecess 1716 configured to receive the protrusion 1714.) When theconductive strip 1706 is broken, it may no longer create a short circuitbetween the two electrical connectors 1712.

Thus, a short circuit as the stimulator probe 1704 is connectedindicates that the stimulator probe 1704 has not been previouslyattached to a stimulator body 1702. Instead, if the stimulator probe1704 is not new and has been previously attached to a stimulator body1702, the conductive strip 1706 may be already broken. Placing the usedstimulator probe 1704 onto the stimulator body 1702 thus may not causethe stimulator circuitry to short circuit. Whether or not this shortcircuit occurs may be detected by any suitable mechanism. For example,the stimulator may comprise a micro-controller, and an analog voltageproportional to the load voltage may be connected to ananalog-to-digital port on the micro-controller. When the stimulatorprobe 1704 is placed onto the stimulator body 1702, the micro-controllermay apply a test voltage across the two electrical connectors 1712. Ifthe connectors 1712 are connected via the conductive strip 1706 (i.e., anew stimulator probe is being place on the stimulator body), the sampledvoltage may be about 0 V. In contrast, if the electrical connectors 1712are not connected via the conductive strip 1706 (i.e., a used stimulatorprobe is being placed on the stimulator body), the sampled voltage willbe greater than about 0 V. This non-zero sampled voltage may beregistered by the micro-controller. If the micro-controller registers anon-zero sampled voltage, it may disable stimulus delivery. As such, themechanical fuse may function as a disabling mechanism that preventsstimulus delivery to the subject when the stimulator probe isreconnected to the stimulator body after being disconnected from thestimulator body. It should be appreciated that the fuse may have othersuitable designs. In some variations, the fuse may comprise anelectrical fuse that may be blown during the initial delivery of astimulus.

One or more mechanisms for determining when a stimulator probe isattached (e.g., a mechanism to record when the stimulator probe isconnected, as described with respect to FIGS. 15B-15C, and/or amechanism to determine when a new probe is attached to the stimulator,as described with respect to FIGS. 17A-17E) may also be used in somevariations to render the stimulator probe inoperable and/or to encouragereplacement of the stimulator probe or a portion thereof (e.g.,disposable prongs or sleeves) after a predetermined number of treatmentsessions, and/or after a predetermined duration of stimulation. In someof these variations, attachment of the stimulator probe may beregistered using one or more of these mechanisms, and the stimulator maybe programmed to measure the duration of stimulation or number oftreatment sessions provided using that stimulator probe. The stimulatormay be configured to do so via intelligence in a control subsystem, suchas a microcontroller, programmable logic (e.g., a field-programmablegate array), or an application-specific integrated circuit (ASIC).

In some variations, the stimulators described here may be configuredsuch that it may be necessary to replace a disposable stimulator probein order to recharge the stimulator or to replace a power supply of thestimulator. For example, in some variations where the stimulatorcomprises one or more electrical contacts or ports configured to connectto an external power source, the stimulator probe may be configured tocover or otherwise block access to the electrical contacts/ports whenthe stimulator probe is connected to the stimulator body. In thesevariations, it may be necessary to remove the stimulator probe toprovide access to the electrical contacts/ports (which may in somevariations disable the stimulator probe, as described in more detailbelow). Similarly, in variations where the stimulator body includes areplaceable power source (e.g., one or more batteries), the stimulatorprobe may block access to the replaceable power source such that thestimulator probe may need to be disconnected from the stimulator bodyprior to replacing the power source.

In variations where a stimulation system comprises a base station (asdescribed in more detail below), a stimulator may be configured suchthat the stimulator cannot be connected to the base station while astimulator probe is attached to the stimulator body. For example, in thevariations of the stimulation systems shown in FIGS. 21A-21D, 22A-22D,and 23A-23B described in more detail below, the base station maycomprise a recess sized and configured to receive the stimulator body tooperationally connect the stimulator body to the base station.Specifically, the recess may be sized such that the stimulator body canfit within the recess when the stimulator probe is disconnected from thestimulator body (as illustrated in FIGS. 21A, 22A, and 23B), but isprevented from fitting in the recess when the stimulator probe isattached to the stimulator body. In these variations, it may benecessary to first disengage the stimulator probe. Accordingly, toutilize one or more functions of the base station, a user may need tofirst decouple a stimulation probe from the stimulator body beforeconnecting the stimulator body to the base station.

In some variations, the stimulator probe may comprise a lockoutmechanism that prevents the stimulator probe from being reconnected tothe stimulator body after being disconnected from the stimulator body.For example, the stimulator may be configured such that the stimulatorprobe is disabled when disengaged from the stimulator body (e.g., whenthe probe is disengaged from the stimulator body in order to connect thestimulator body to the base station). This may prevent the stimulatorprobe from being reused. For example, in the variation of the stimulatorsystem 2300 in FIGS. 23A-23B, the disposable stimulator probe 2306 maycomprise a frangible connector 2318 (which in some instances may alsoact as a lead to connect an electrode to the stimulator body 2304). Thefrangible connector 2318 may connect to the stimulator body 2304 toreleasably couple the stimulator probe 2306 to the stimulator body 2304.The stimulator 2302 may be configured such that frangible connector 2318is broken when the stimulator probe 2306 is disengaged from thestimulator body 2304. For example, the stimulator body 2304 may comprisea release mechanism 2320, such that the release mechanism 2320 decouplesthe stimulator probe 2306 from the stimulator body 2304 and breaks thefrangible connector 2318. With the frangible connector 2318 broken, thestimulation probe 2306 may be prevented from being reconnected to thestimulator body 2304. Additionally or alternatively, when the stimulatorprobe is disconnected from the stimulator body, one or more of theelements holding the stimulator probe and stimulator body may break orbe otherwise deformed. For example, in some variations stimulator 100may be modified such that one or more of the tabs 196 or 198 may breakoff of the stimulator probe 104 when the stimulator probe is removedfrom the stimulator body 102. This may prevent the stimulator probe 104from being securely reconnected to the stimulator body 102.

Cap & Case

In some variations, the stimulators described here may comprise a cap toprotect the stimulator probe. For example, FIGS. 19A and 19B showperspective and front views, respectively, of stimulator 100 with anattached cap 1900. As shown there, the cap 1900 may fit over thestimulator probe 104, which may protect the probe from contamination.More particularly, it may be desirable for the cap to protect the nasalinsertion prongs, and especially the electrodes, from contamination. Thecap 1900 may have any suitable shape. In some variations, the cap 1900may cover the operating mechanisms when attached to the stimulator. Thismay prevent the operating mechanisms from being inadvertently oraccidentally manipulated. As shown in FIGS. 19A-19B, the cap 1900 maycover the buttons 114 and 116 of the stimulator body 102, while leavingthe sides of stimulator body 102 exposed. This may allow a user to moreeasily grip the stimulator body 102 in order to remove the cap 1900. Insome variations the cap may comprise a texturized surface or othergripping features to assist with removal, such as ridges 1904 shown oncap 1900. The cap or other enclosure may comprise any suitable materialor materials, such as a plastic or synthetic resin. In some variationsthe cap or other enclosure may be translucent or transparent, while inother variations it may be opaque.

The cap or other enclosure may in some variations comprise one or morefeatures to control the exposure of the stimulator probes to the air.When the probes comprise a hydrogel or other liquid or wet material, theamount of exposure of air may affect the rate at which the hydrogel orother liquid or wet material dries out. For example, in some variationsthe caps may comprise one or more openings to allow for air flowunderneath the cap or other enclosure. Cap 1900, for example, maycomprise an opening 1902 at the distal end of the cap. In somevariations the cap may be generally conformed to the shape of thestimulator probe (e.g., by comprising recesses having shapescorresponding to the stimulator prongs' shape and configured to receivethe prongs), such that the air within the cap is minimal; in othervariations, the cap may not be conformed to the shape of the stimulatorprobe, such that there is more air circulating within the cap around thestimulator probe.

In some variations, the cap may comprise one or more features to promoteattachment of the cap to the stimulator body. For example, in somevariations the cap may comprise tabs or bosses, which may be configuredto mate with indentations or cavities on the stimulator. Additionally oralternatively, the stimulator may comprise tabs or bosses, which may beconfigured to mate with indentations or cavities on the cap. In some ofthese variations, the flexibility of the cap material may allow cap tobe placed on the stimulator. Additionally or alternatively, the cap maycomprise one or more living hinges or cutaways 1906 and 1908, such asshown in FIG. 19C. The living hinges or cutaways may allow the cap toflex in order to slide past a raised feature on the stimulator (e.g., atab or boss); for example, squeezing the top cutaway 1906 may cause thebottom portion 1908 to rotate away from the stimulator, allowing thebottom portion 1908 to slide past a raised feature when attaching orremoving the cap 1900. Additionally or alternatively, the cap materialand/or shape may promote attachment of the cap to the stimulator body.For example, the cap may be flexible in order to flex to slide over athicker portion of the stimulator while being attached, and then the capmay relax into a conformal position upon reaching a thinner portion ofthe stimulation.

In yet other variations, the cap or enclosure may comprise two or morepieces, which may be connected to cover all or a portion of thestimulator. In some variations, the two or more pieces may be fullyseparable, while in other variations the pieces may be permanentlyconnected (e.g., via a hinge). An example of an enclosure comprising twopieces is shown in FIG. 20. FIG. 20 shows a perspective view of thestimulator of FIGS. 9A-9F with another variation of enclosure. As shownthere, the enclosure 2000 may comprise a cover 2002 configured toreceive the stimulator probe 900, and a cover lid 2004 configured toattach to the cover 2002 to protect the stimulator probe 900. In thevariation shown in FIG. 20, the cover lid 2004 may slide onto the cover2002. As shown, the enclosure 2000 may comprise an opening configured toallow the cable connectors 944 to extend out of the enclosure 2000. Inother variations, the cap or enclosure may comprise a top portion and abottom portion that may connect in the middle to enclose the stimulator.

Additionally or alternatively, the stimulation systems described heremay comprise a case configured to hold the stimulator. Like a cap, acase may protect the probe (more particularly, the nasal insertionprongs) from contamination. In some variations, the case may beconfigured to hold the stimulator while the stimulator has a capattached. On such variation is shown in FIG. 36A, which shows astimulator 3600 sitting within a case 3602. As shown, the stimulator3600 may be placed into a recess of the case 3602 with a cap 3604attached. The case 3602 may latch closed in order to protect thestimulator 3600. In other variations, the case may be configured to holdthe stimulator without a cap attached, as shown in FIG. 36B. As shownthere, a case 3652 may comprise a recess 3656 configured to receive astimulator 3650 without a cap. In yet other variations, the case may beconfigured to hold a stimulator body and a stimulator probe whendisconnected. In some variations, the case may be configured to chargethe stimulator in variations in which the stimulator comprises arechargeable power source. In these variations, the case may comprise arecess configured to receive a stimulator body. The case may compriseone or more electrical contacts configured to connect to one or morecorresponding electrical contacts on the stimulator body, or thestimulator body and case may be configured such that the case mayinductively charge the stimulator (as described in more detail withregard to the base station herein), and the case may comprise a powersource and/or a port configured to connect to a power source. In somevariations, the case may contain compartments, recesses, or the like tohold accessories, such as but not limited to tools for cleaning thenasal insertion prongs (e.g., alcohol wipes), additional disposablecomponents (e.g., stimulator prongs, sleeves), a connector cable, or thelike.

Base Station

In some variations, the stimulation systems described here may comprisea base station configured to connect to a portion of the stimulator, thestimulator having a stimulator body and a stimulator probe. The basestation may be configured to releasably connect to one or more portionsof the stimulator, and may be configured to perform one or morefunctions when connected to the stimulator. FIGS. 21A-21D depict aportion of a stimulator system comprising a base station 2100 asdescribed here. FIG. 21A shows a front view the stimulator body 2102docked in the base station 2100, while FIGS. 21B, 21C, and 21D depictside, back, and top views of the base station 2100, respectively. Thestimulator body 2102 and stimulator probe (not shown) may include any ofthe elements of the stimulators described herein. In variations wherethe stimulator body 2102 comprises a rechargeable power source (such asa rechargeable battery, capacitor, or the like), the base station 2100may be configured to recharge the rechargeable power source. Forexample, the base station 2100 may comprise one or more electricalcontacts 2104, which may be configured to electrically connect tocorresponding electrical contacts on the stimulator body 2102. In somevariations, these electrical contacts may be the same electricalcontacts that connect the stimulator probe and the stimulator body(e.g., electrical contacts similar to connectors 122 and 124 ofstimulator 100). This electrical connection may allow the base station2100 to charge the power source of the stimulator body 2102.

In some variations, the base station may comprise a safety mechanismthat prevents power delivery to the electrical contacts unless thestimulator is connected. For example, the base station may comprise asensor configured to detect the stimulator. After the stimulator isdetected, power may be delivered to the contacts. In one variation, thesensor may comprise a magnetic field sensor (e.g., a Hall effectsensor), and the stimulator may comprise a magnet. When the stimulatoris placed in the base station, the magnetic field sensor may detect thepresence of the magnet in the stimulator and may in turn cause power tobe delivered to the contacts.

It should be appreciated that in other variations, the base station mayadditionally or alternatively be configured to inductively charge thestimulator. For example, the base station may comprise a primary coil,which may or may not be wrapped around a ferromagnetic (e.g., iron)core, and the stimulator body may comprise a secondary coil, which mayor may not be wrapped around a ferromagnetic core. When the stimulatorbody is placed in the base station, the coils and iron cores may form acomplete transformer, allowing power to be inductively transferred fromthe base station to the stimulator body. Additionally or alternatively,it should be recognized that inductive power transfer may also be usedto transfer power from the stimulator body to the stimulator probe, asdescribed in more detail above.

The base station may be powered in any suitable manner. In somevariations, the base station may be connectable to an external powersource (e.g., a wall outlet or separate battery back), which may providepower to the stimulator and/or the base station. In some variations, thebase station may comprise a power cable, which may be permanentlyattached via a strain relief. In other variations, such as the variationof the base station 2100 shown in FIGS. 21A-21D, the base station maycomprise a port 2106 (e.g., a USB port or micro-USB port), which mayconnect the base station 2100 to an external power source. It should beappreciated that the base station 2100 may include any suitable port orconnector for connecting the base station to an external power source.Additionally or alternatively, the base station may comprise a powersource (e.g., one or more batteries) operable to power the base station2100 (and to recharge the stimulator in variations where the stimulatoris rechargeable). The power source may or may not be rechargeable.

The base station 2100 may be configured to rest on a surface (e.g., acounter or table), and may comprise a weight and/or a bottom surfacewith increased friction (e.g., a rubber pad 2108) to help keep the basestation 2100 in place. In variations in which the stimulator comprises amagnet or material attracted to a magnetic field (e.g., iron, nickel,cobalt, alloys thereof and the like), the base station may comprise amagnet in a corresponding location in order to hold the stimulator inplace within the base station. For example, the base station maycomprise a magnet located between the electrical contacts, which may beconfigured to attract a magnet in the stimulator body (e.g., in a basestation configured to receive stimulator body 102, the base station maycomprise a magnet configured to attract the magnet 134 attached to theinterior of proximal housing 142.).

FIGS. 22A-22D depict another variation of a stimulator system comprisinga base station as described here. FIG. 22A shows a front view thestimulator body 2202 docked in the base station 2200, while FIGS. 22B,22C, and 22D depict top, bottom, and side views of the base station2200, respectively. The base station 2200 may have similar features asbase station 2100 described above but may be have a different shapeconfigured to lie on its side on a surface, as opposed to having a flatbottom surface. Like base station 2100, it may be configured to connectto stimulator body 2202 via electrical contacts 2204 and may comprise aport 2206 to connect the base station 2200 to an external power source(e.g., via a USB cable 2210). The base station 2200 may comprise and amagnet in order to hold the stimulator in place. In some variations, thebase station 2200 may comprise ribs 2208 to help the user grip the basestation 2200 in order to remove the stimulator body 2202 from the basestation 2200.

In instances where the stimulator is configured to record or otherwisestore data (e.g., the frequency or duration of stimulation), the basestation may be configured to retrieve data from the stimulator. Forexample, in variations where the stimulator and base station areconfigured to be electrically connected, data may be transmitted viathis electrical connection (e.g., the connection between connectors 122and 124 of stimulator body 102 and electrical contacts 2104 of basestation 2100 or electrical contacts 2204 of base station 2200). FIG. 18illustrates a schematic diagram of stimulator circuitry allowing for thesame pins 1802 to be used to transfer data from the stimulator body tothe base station, to transmit a stimulus from the stimulator body to thestimulator probe, and to charge a rechargeable power source in thestimulator body using the base station. As shown, the pin drivers 1804may take input signals either from a data communication subsystem 1806or a stimulation subsystem 1808. The input to the drivers 1804 may bedetermined by a switch 1810. In some variations, the switch 1810 maycomprise a gate, state machine, or a micro-controller. The pins 1802 mayalso be used to charge the stimulator. A rectification circuit 1812 maybe configured to rectify a charging input signal without interferingwith any output stimulation or data waveform. In some variations, therectification circuit may comprise a full wave rectifier comprisingrectification diodes, but it should be appreciated that any suitablecircuit may be used. Time blocks for each function may be synchronizedin order for the system to perform each function.

Additionally or alternatively, the base station may be configured towirelessly transmit or receive data from the stimulator. In variationswhere data may be transmitted between the stimulator and the basestation, the base station may be configured to provide programminginstructions to the stimulator. The base station may be configured to beattached to an external computing device, to transfer data downloadedfrom the stimulator and/or receive programming instructions to beprovided to the stimulator. In variations where the base stationcomprises a port (such as a USB port), the port may be used to attachthe base station to an external computing device.

In some variations, the base station may be configured to perform one ormore diagnostic tests on the stimulator when the stimulator is connectedto the base station. For example, FIGS. 23A-23B show a variation of astimulator system comprising a base station that may be configured totest the operational status of the stimulator, and alert a user as towhether the stimulator is ready for subsequent use. In the variation ofthe base station shown in FIGS. 23A-23B, the base station 2308 maycomprise a recess 2322 configured to receive the stimulator body 2304when the stimulator probe 2306 is detached from the stimulator body2304. The base station 2308 may comprise one or more electrical contacts2310, which may be configured to electrically connect to correspondingelectrical contacts 2312 on the stimulator body 2304. The base station2308 may comprise a test button 2314 and one or more status indicators2316. A user may press or otherwise activate the test button 2314 toinitiate a diagnostic test of the stimulator 2302 when stimulator body2304 is placed into recess 2322 (as shown in FIG. 23B).

The status indicators 2316 may communicate the results of the diagnostictest to the user. For example, in some variations the status indicators2316 may comprise a first light and a second light, wherein the firstlight is activated when the diagnostic test determines that thestimulator 2302 is operational, and the second light is activated whenthe diagnostic test results in an error or otherwise determines that thestimulator 2302 is not presently operational. In other variations, thestatus indicator 2316 may include a single light that changes colordepending on the results. It should be appreciated that the base station2308 need not provide visual status indicators to the user, and may beconfigured to provide feedback in any suitable manner (e.g., via visualfeedback, auditory feedback, tactile/vibratory feedback, combinationsthereof and the like). It should be appreciated that the base stationsdescribed herein may be configured to receive/connect to the handheld orthe implantable stimulators as described here.

In some variations, the systems described here may further comprise acap configured to fit over the stimulator while the stimulator isconnected to the base station. The cap may attach to the base station,and may assist in securing the stimulator to the base station. In somevariations, the cap may be translucent or transparent, while in othervariations, the cap may be opaque for discreteness. Additionally oralternatively, the base station may comprise a recess configured toreceive another portion of the stimulation system, such as a stimulatorprobe or a cap.

External Device Connection

In some variations the stimulators described here may be configured toconnect to an external device, such as a mobile device (e.g., a cellulartelephone, a tablet, a wearable computer (e.g., optical head-mounteddisplays such as Google Glass™), or the like), a computer, or the like.The stimulators may be configured to connect to an external devicethrough any suitable connection method. In some variations theconnection method may be wireless (e.g., via WiFi, Bluetooth, or thelike), and the stimulator may comprise an antenna or the like.Additionally or alternatively, the connection method may be via a wiredtransmission line. In these variations, the stimulator may comprise oneor more ports (e.g., a USB port), connectors and/or cables configured tophysically connect the stimulator to an external device. In somevariations, the stimulators may use a wireless or wired connection toconnect to the internet, via which they may be connected to an externaldevice. In these variations, the device may be at a distant location(e.g., at the manufacturer, at a physician's office, or the like).

In instances in which the stimulators are configured to connect to anexternal device, the device may be configured to perform one or moreoperations associated with the stimulator. For example, in variationswhere the stimulator is configured to collect data (e.g., one or moresubject parameters, stimulation timing or parameters, stimulatordiagnostic information, such as described in more detail herein) andstore that data in a memory unit of the stimulator, connection of thestimulator to the device may allow for transfer of data stored in thestimulator's memory unit to the device. Specifically, the device andstimulator may be programmed such that upon connection of the device andthe stimulator, the device may download the recorded data stored in thestimulator's memory. In some variations, once data has been transferredfrom the stimulator to the device, the stimulator may be configured todelete this data from the stimulator memory. Because the amount ofmemory available in the device may be greater than that in thestimulator, this transfer may increase the data that may be accumulatedfor a subject.

In addition to or instead of transferring data stored in the stimulatormemory, a device may be configured to collect and store real-time datafrom the stimulator when the two are connected. In some of thesevariations, the stimulator may also be configured to store this data inthe stimulator memory. In some instances, the device may be configuredto transmit data (e.g., via internet connection, cellular data network,or the like) from the device to an external location (e.g., to adatabase where the data may be analyzed, to a physician's office toallow the physician to monitor the data and, in some instances, providefeedback).

In some variations, the device may be configured to solicit input from auser. For example, if the stimulator is used to provide stimulationwhile attached to a device, the device may be configured to solicit theuser to input data regarding the subject's experience (e.g., a subject'slevel of comfort/discomfort, status of subject's symptoms). In somevariations, the device may be configured to present data (and/oranalysis of the data) to a user. For example, the device may beconfigured to display information regarding the frequency ofstimulation, the average duration of stimulation, a graph of subjectcomfort levels over time, or the like. In some variations, the devicemay be configured to share the data or analysis of the data with themanufacturer, clinicians, friends, or others.

Implantable Stimulators

In some variations of the stimulation systems described here, thestimulation system may comprise a stimulator configured to be implanted,either permanently or temporarily, in a subject. It should beappreciated that the implantable stimulators need not be surgicallyimplanted. In some of these instances, the implantable stimulator may beconfigured such that the stimulator may be inserted and/or removed by auser. In others of these instances, the implantable stimulator may beconfigured to be inserted and/or removed by a medical professional. Inother instances, the stimulator may be configured to be implanted in orotherwise attached to tissue within a nasal or sinus cavity.

As mentioned above, in some variations an implantable stimulator may beconfigured for placement and/or removal by a user. For example, FIG. 25depicts a cross-sectional view of a user's nose having a septum 2508 andnostrils 2510 and 2512 having a variation of an implantable stimulator2500 located therein. As shown there, the stimulator 2500 may comprise aclip 2502, a first stimulator unit 2504 attached to a first end of theclip 2502, and a second stimulator unit 2506 attached to a second end ofthe clip 2502. Generally, the clip 2502 may be configured to temporarilyconnect the stimulator 2500 to a nasal septum 2508 of a user, which mayposition the first stimulator unit 2504 in the first nostril 2510 andthe second stimulator unit 2506 in the second nostril 2512.

In some variations, the clip 2502 may comprise a u-shaped portion 2514configured to receive and clamp to a portion of the nasal septum 2508.This engagement between the clip 2502 and the nasal septum 2508 maylimit advancement of the stimulator 2500 into the nose (e.g., to preventover-insertion of the stimulator 2500). The clip 2502 may exertsufficient pressure on the septum 2508 so as to resist removal of thestimulator 2500 from the nose. Accordingly, the clip 2502 may allow thestimulator to be positioned in the nose of a user, and the user may wearthe stimulator for as long as needed without needing to actively holdthe stimulator in the nose. The clip 2502 may be removed by flexing theclip 2502 to disengage it from the septum. As such, the patient may beable to insert and remove the stimulator 2500 him- or herself. In somevariations, the clip 2502 may be at least partially formed from one ormore shape memory materials (e.g., a nickel-titanium alloy), such thatthe clip 2502 may be deformed to disengage the clip 2502 from the septum2508 and may return to its original shape. In some variations, the clip2502 may be curved such that the stimulation unit or units are directedtoward the front of the septum, as described herein. In some variationsin which the stimulator 2500 is configured to deliver an electricalstimulus, an exterior portion of the clip 2502 may be formed from one ormore insulating materials, such as described herein (e.g., PTFE,silicone, combinations thereof, or the like), and an interior portionmay include an electrically conductive core (e.g., a wire of anysuitable metal, such as silver, stainless steel, platinum, alloysthereof, or the like) electrically connecting the first stimulator unit2504 to the second stimulator unit 2506. In these variations, theinsulating outer portion of the clip 2502 may prevent inadvertentelectrical stimulation between the clip 2502 and the subject.

While shown in FIG. 25 as having a first stimulator unit 2504 and asecond stimulator unit 2506, it should be appreciated that in somevariations the stimulator 2500 may comprise only a first stimulator unit2504. Generally, when the stimulator is configured to deliver anelectrical stimulus, each stimulator unit may comprise one or moreelectrodes 2516. While shown in FIG. 25 as being formed from anexpandable wire mesh/braid electrode, each electrode 2516 may beconfigured in any manner as described in more detail herein. Forexample, in some variations, it may be desirable for the stimulatorunits to comprise a smooth surface to prevent tissue abrasion. In somevariations, it may be desirable for the stimulator units to comprise aradially expandable structure that may expand to contact the nasalmucosa when inserted into the nostrils. Additionally or alternatively,it may be desirable for the electrode to be directed toward the front ofthe nose (e.g., by the electrode comprising only a front-facing portionof the stimulator unit), as described in more detail herein. When thestimulator comprises only a first stimulator unit 2504, the firststimulator unit 2504 may provide unilateral stimulation to the firstnostril 2510 via electrodes of the first stimulator unit 2504. Invariations where the stimulator 2500 comprises first 2504 and second2506 stimulator units, the stimulator may be configured to provideunilateral stimulation of the first nostril 2510 (e.g., via electrodesof the first stimulator unit 2504, with a return electrode in the firstnostril or elsewhere), unilateral stimulation of the second nostril 2512(e.g., via electrodes of the second stimulator unit 2506, with a returnelectrode in the second nostril or elsewhere), or bilateral stimulation(e.g., via electrodes of the first 2504 and second 2506 stimulatorunits). The stimulator may be configured such that the electrodes 2516are placed in contact with any suitable tissue structure or structures(e.g., the nasal mucosa above the columella, such as the nasal mucosasuperior to the columella (e.g., the nasal mucosa near the interfacebetween the nasal bone and the upper lateral cartilage) when the clip2502 is connected to the nasal septum.

Generally, the first 2504 and/or second 2506 stimulator units maycomprise a housing 2520, which may include any of the control circuitrydescribed with respect to the handheld stimulators described here. Forexample, the stimulator may comprise a control subsystem having aprocessor, a stimulation subsystem, and a memory. In some variations thecontrol subsystem may have a detection subsystem. Additionally oralternatively, the stimulator may comprise a communication subsystem. Insome of these variations, the stimulator may be configured to wirelesslyreceive and/or transmit data and/or power via a coil 2518 or otherantenna. For example, in some of these variations, the stimulator may beconfigured to connect to an external device (such as an externalprogrammer, laptop or other computer, or to a mobile device, asdiscussed in more detail herein). The stimulator circuitry may be housedin a single housing 2520 (e.g., a housing 2520 of the first stimulatorunit 2504 or a housing 2520 of the second stimulator unit), or may bedivided between multiple housings (e.g., a housing 2520 of the firststimulator unit 2504 and a housing 2520 of the second stimulator unit).

In some variations, the stimulator 2500 may comprise a power source(e.g., a battery) (not shown). In other variations, the stimulator 2500may be powered wirelessly (e.g., via power received from a coil 2518 orother antenna), such as described in U.S. patent application Ser. No.13/441,806, filed on Apr. 6, 2012, and titled “Stimulation Devices andMethods”, the contents of which is hereby incorporated by reference inits entirety.

FIGS. 26A-26C depict another variation of an implantable stimulator 2600configured for placement and/or removal by a user. As shown there, thestimulator 2600 may comprise a clip 2602, a first stimulation unit 2604attached to a first end of the clip 2602, and a second stimulation unit2606 attached to a second end of the clip 2602. Generally, the clip 2602may be configured to temporarily connect to a nasal septum of a user,which may position the first stimulation unit 2604 in a first nostril ofthe user and the second stimulation unit 2606 in a second nostril of theuser, as shown in FIG. 26B.

The clip 2602 may comprise a first arm 2608 and a second arm 2610, whichmay be connected at the base of the clip 2602. This may limit theadvancement of the clip 2602 into the nose. The first 2608 and second2610 arms may curve inwardly toward each other. This curvature may causethe stimulation units 2604 and 2606 to press against the septum of theuser when inserted, which may hold the clip 2602 in place and allow thestimulator to be worn in place by the user as long as needed without theuser needing to actively hold the stimulator in his/her nose. The clip2602 may be removed by pulling it downward and/or flexing the clip 2602to disengage it from the septum. The first 2608 and second 2610 arms mayalso curve forward when placed in the user's nose. This may cause thestimulation units to contact a desired region of the nasal tissue (e.g.,the front of the nasal septum) when the clip is connected to the nasalseptum. In some variations in which the stimulator 2600 is configured todeliver an electrical stimulus, the exterior portion of the first 2608and second 2610 arms may be formed from one or more insulatingmaterials, while the interior portion may comprise an electricallyconductive core, as described in more detail with respect to implantableclip 2502.

When the stimulator 2600 is configured to deliver an electricalstimulus, the stimulation units 2604 and 2606 may comprise electrodes.The electrodes may have any suitable design. A shown in FIGS. 26A and26C, the electrodes may in some variations be spherical, although inother variations the electrodes may be cylindrical, an arc of acylindrical surface, elliptical, ovoid, or the like, and/or may comprisean array of electrodes. In some variations, the electrodes may comprisean expandable wire mesh/braid electrode, as described with respect tostimulator 2500. The electrodes may comprise one or more conductivematerials, including but not limited to conductive metals (e.g.,stainless steel, titanium, tantalum, platinum or platinum-iridium, otheralloys thereof, or the like), conductive ceramics (e.g., titaniumnitride), liquids, gels, or the like. In some variations, the electrodemay comprise one or more materials configured to promote electricalcontact between electrodes of the stimulator probe and tissue (i.e., allof an electrodes or a portion of the electrode, such as a covering),such as a hydrogel skin, foam or porous material impregnated with a gelor liquid, or the like, as described in more detail with respect tohandheld stimulators.

The clip 2602 may further comprise an electrical connector that may bereversibly connectable to a handheld stimulator body 2614. In somevariations, as shown in FIG. 26C, the electrical connector may comprisea lead 2612 extending from the base of the clip 2602. In othervariations, the electrical connector may comprise one or more conductiveareas on the clip 2602 (e.g., areas without insulation). The stimulatorbody 2614 may comprise an array of contacts 2616 configured to connectto the electrical connector of the clip 2602. In some variations, thestimulation units 2604 and 2606 may act as return electrodes. In othervariations, the stimulator 2600 may comprise a distant return (e.g., theconductive bar 2618, which may be in contact with the user's hand). Thehandheld stimulator body 2614 may have any of the control circuitrydescribed with respect to the handheld stimulators described. When thestimulator 2600 is configured to deliver an electrical stimulus, thestimulator body 2614 may generate an electrical stimulus that may betransmitted to the electrodes 2604 and 2606 via the first 2608 andsecond 2610 arms.

FIGS. 27A-27D show another variation of an implantable simulator 2700.FIGS. 27A and 27B show side views of the implantable stimulator, whileFIGS. 27C and 27D show front views of the stimulator 2700. As shownthere, the stimulator 2700 may comprise a housing 2702 and a pair ofexpandable electrodes 2704. Generally, the housing 2702 may house any ofthe control circuitry as described herein, which may be connected to theelectrodes 2704 such that the stimulator 2700 may deliver stimulation totissue via the electrodes 2704. In some variations, the stimulator 2700may comprise a coil 2706 or other antenna which may allow the stimulator2700 to wirelessly communicate with an external device (not shown), suchas described in more detail herein.

Generally, the expandable electrodes may be moveable between alow-profile configuration (as shown in FIGS. 27A and 27C) and anexpanded configuration (as shown in FIGS. 27B and 27D). In someinstances, the electrodes may be configured to self-expand from thelow-profile configuration to the expanded configuration. Additionally oralternatively, another device (such as a balloon catheter) may beconfigured to expand the electrodes between the low-profile and expandedconfigurations. When expanded, the electrodes 2704 may act as an anchorto help hold the stimulator 2700 in place relative to the body. In somevariations, it may be desirable for the stimulator units to comprise asmooth surface to prevent tissue ingrowth. For example, as shown in FIG.27E, the stimulator 2700 may be positioned in a nasal cavity 2708, andthe electrodes 2704 may be expanded to anchor the stimulator 2700 in thenasal cavity 2708. In some variations, this may position one or moreportions of the electrodes 2704 in contact with nasal mucosal tissue(e.g., tissue of one or more nasal turbinates 2710), which may allow theelectrode 2704 to deliver stimulation to the nasal tissue. A stimulatormay be positioned in one nostril to deliver unilateral stimulation, or astimulator may be positioned in each nostril to provide bilateralstimulation. In other instances, a stimulator may be positioned at leastpartially in a sinus cavity.

The stimulator 2700 may be delivered in any suitable manner. Forexample, FIG. 28 shows one variation of a delivery system 2800 suitablefor use in delivering the stimulator. As shown there, the deliverysystem 2800 may comprise a guide catheter 2802. The guide catheter 2802may be flexible and may be biased toward a configuration comprising apre-set curve 2804, such that when inserted into the nostril 2806 of asubject, a distal portion of the guide catheter 2802 may be positionedat a desired implantation location (e.g., between turbinates 2812). Insome variations, the guide catheter 2802 may comprise a stop sleeve2808, which may be configured to limit advancement of the guide catheter2802 into the nose.

With a guide catheter 2802 positioned in the nasal cavity, a stimulator(such as implantable stimulator 2700) may be advanced out of a lumen ofthe guide (e.g., via a pusher or an endoscope 2810), and a firstelectrode (or anchor) of the stimulator may be expanded to anchor thefirst electrode in the nasal cavity. The guide catheter 2802 may bewithdrawn to release a second electrode (or anchor) of the stimulator toanchor the second electrode in the nasal cavity. Once the stimulator isdelivered to the nasal cavity, the guide catheter 2802 may be withdrawn.In some variations, one or more steps may be visualized using anendoscope 2810, which in some instances may be positioned at leastpartially through the guide catheter 2802.

While the electrodes 2704 of the stimulator 2700 shown in FIGS. 27A-27Emay be configured to be expandable, the electrodes 2704 need not be. Insome variations, the stimulator may comprise one or more expandableanchors which may be separate from one or more electrodes of thestimulator. Additionally or alternatively, the stimulator may compriseone or more ribs, stubs, hooks, or barbs which may help to anchor thestimulator in the body.

When the electrodes 2704 are configured to be expandable, they may beformed from any suitable expandable structure. For example, in thevariation of the stimulator 2700 shown in FIGS. 27A-27E, the electrodes2704 may each comprise an expandable braid. In some variations, thebraid may be formed from a braided shape memory wire (e.g., anickel-titanium alloy), which may overlaid with one or more electricallyconductive materials (e.g., platinum, a platinum-nickel-titanium alloy,or the like).

In other variations, the electrodes may be formed from an expandabletube. For example, FIG. 24 shows a variation of a stimulator 2400comprising a housing 2402 and expandable electrodes 2204. As shownthere, each electrode 2204 may be formed from a tube, which may beconfigured to move from a low-profile configuration (as shown in theleft electrode 2204 in FIG. 24) and an expanded configuration (as shownin the right electrode 2204 in FIG. 24). In some variations, the tubemay be a laser cut tube, which may be formed from a shape memorymaterial (such as a nickel titanium alloy), which may be overlaid withone or more electrically conductive materials (e.g., stainless steel,titanium, tantalum, platinum or platinum-iridium, other alloys thereof,titanium nitride, liquids, gels, or the like). In still othervariations, an electrode may be formed at least partially from anexpandable foam, which may be impregnated with one or more conductivegels or fluids as discussed in more detail herein.

In still other variations, the stimulation systems described here maycomprise a stimulator that is configured to be implanted within orbeneath mucosal tissue. The stimulator may be implanted in a nasal orsinus cavity, and may be placed within the mucosa, beneath the mucosa,between mucosa and bone and/or cartilage, within the cartilage, or thelike. Generally, the stimulator may comprise a stimulator body and oneor more electrodes, and may include any of the stimulators described inU.S. patent application Ser. No. 13/441,806, filed on Apr. 6, 2012 andtitled “Stimulation devices and methods”, which was previouslyincorporated by reference in its entirety.

Stimulation Methods

Generally, the stimulators and stimulation systems described herein maybe configured to stimulate nasal or sinus tissue. In some variations,the stimulation may be used to cause tear production by a user.Generally, a stimulator (such as described above) may be configured tostimulate one or more nasal or sinus afferents which may activate alacrimation response via a nasolacrimal reflex. In some instances, thismay comprise stimulating one or more branches of the trigeminal nerve ortrigeminal nerve afferents. In some of these instances, this maycomprise stimulating the ophthalmic branch of the trigeminal nerve. Thisstimulation may be used to treat various forms of dry eye, including(but not limited to), chronic dry eye, episodic dry eye, seasonal dryeye, aqueous deficient dry eye, or evaporative dry eye.

In some instances, the stimulation may be used as a prophylactic measureto treat users which may be at an increased risk of developing dry eye,such as subjects who will undergo or who have undergone ocular surgerysuch as refractive vision correction and/or cataract surgery. In otherinstances, the stimulators may be used to treat ocular allergies. Forexample, an increase in tear production may flush out allergens andother inflammatory mediators from the eyes. In some instances, thestimulation delivered by the stimulators described herein may beconfigured to cause habituation of the neural pathways that areactivated during an allergic response (e.g., by delivering a stimulationsignal continuously over an extended period of time). This may result inreflex habituation which may suppress the response that a user wouldnormally have to allergens.

Location

When an implantable stimulator is used to provide stimulation, theimplantable stimulator may be positioned in a nasal or sinus cavity (ormultiple nasal or sinus cavities). When a handheld stimulator is used toprovide stimulation, one or more prongs of the stimulator may beinserted at least partially into the nose of a user, and a stimulationsignal (such as described above) may be delivered to the mucosal tissue.

A portion of the nasal insertion prong(s) may be positioned and/ormanipulated to be placed in contact with any suitable tissue. (Invariations in which the stimulators are configured to deliver anelectrical stimulus, the stimulators may be positioned and/ormanipulated to position electrodes into contact with any suitabletissue.) FIGS. 34A-34C illustrate anatomical locations. For example, thenasal insertion prong(s) may be placed in contact with the upper lip3402, external nasal skin 3404, nasal ala 3406, mucosa of a nasalturbinate (e.g., one or more of the inferior 3408, medial 3410, orsuperior turbinates 3412), or the like. When the stimulators are used toproduce a tearing response as discussed herein, it may be desirable toposition a portion of the nasal insertion prongs (e.g., an electrode) incontact with the nasal mucosa of a nasal turbinate. In some instances,the targeted area may comprise tissue innervated by the anteriorethmoidal branch of the nasociliary nerve, as shown by shaded area 3420in FIG. 34C. In some instances, the targeted area of the nasal mucosamay be superior to the columella 3414. In some of these instances, thetargeted area may be near the inferior end of the nasal bone 3416 (i.e.,near the interface between the nasal bone 3416 and the upper lateralcartilage 3418). In other variations, the targeted area may be thecolumella. In some variations, it may be desirable to place a portion ofthe nasal insertion prong(s) (e.g., an electrode) between about 20 mmand about 35 mm into the nasal cavity of the subject. In some of thesevariations, it may be desirable to place an electrode between about 25mm and about 35 mm into the nasal cavity of the subject. As describedherein, it may in some instances be desirable to direct the nasalinsertion prongs such that a portion (e.g., the electrodes) is directedtoward the front of the nose. This may allow for selective activation ofnerves in the front of the septum (e.g., the ophthalmic branch of thetrigeminal nerve) while minimizing activation of nerves toward the rearof the nasal septum, which may reduce negative side effects that mayoccur from stimulation of nerves that innervate the teeth, and which mayreduce rhinorrhea. It may also in some instances be desirable to directthe nasal insertion prongs so as to reduce negative side effects thatmay occur from stimulation of the olfactory area.

Electrical Stimulus

In some variations, the stimulation may be delivered unilaterally (e.g.,in a single nostril). For example, in variations where a stimulatorcomprises a single prong, the prong may be placed in a first nostril,and stimulation may be delivered to the first nostril via the prong. Itshould be appreciated that in some of these variations in which thestimulus is electrical, a pad electrode or other return electrode may betemporarily affixed to or otherwise be placed in contact with anexternal portion of the nose to act as a return electrode. In somevariations where a stimulator comprises two or more prongs, each of theprongs may be placed in a first nostril, and some or all of the prongsmay be used to deliver stimulation to mucosal tissue. In othervariations where a stimulator comprises two or more prongs, at least oneprong may be positioned in a first nostril, and at least one prong maybe positioned in a second nostril. In variations in which the stimulusis electrical, some or all of the prongs in the first nostril may beused to deliver unilateral electrical stimulation to the first nostril(e.g., the prongs in the second nostril may remain inactive), or some orall of the prongs in the second nostril may be used to deliverunilateral electrical stimulation to the second nostril.

In some variations, the stimulator may be used to provide bilateralstimulation of the mucosal tissue. In these variations, at least oneprong of the stimulator may be positioned in a first nostril and atleast one prong of the stimulator may be positioned in a second nostril.In these variations, when the stimulus is electrical, electricalstimulation may be delivered between the prongs in the first nostril andthe prongs of the second nostril, which may cause current to flowthrough the septum.

Electrical Stimulus: Waveforms

When the stimulus is electrical, the electrical stimulus delivered bythe stimulators described here may include a waveform or waveforms,which may be tailored for specific treatment regimens and/or specificsubjects. The waveforms may be pulse-based or continuous. It should beappreciated that the waveforms described here may be delivered via abipolar configuration or a monopolar configuration. When the stimulatoris configured to deliver a continuous waveform, the waveform may be asinusoidal, quasi-sinusoidal, square-wave, sawtooth/ramped, ortriangular waveform, truncated-versions thereof (e.g., where thewaveform plateaus when a certain amplitude is reached), or the like.Generally, the frequency and peak-to-peak amplitude of the waveforms maybe constant, but in some variations the stimulator may be configured tovary the frequency and/or amplitude of the waveform. This variation mayoccur according to a pre-determined plan, or may be configured to occurrandomly within given parameters. For example, in some variations thecontinuous waveform may be configured such that the peak-to-peakamplitude of the waveform varies over time (e.g., according to asinusoidal function having a beat frequency). In some instances varyingthe amplitude and/or frequency of a stimulation waveform over time, orpulsing the stimulus on and off (e.g., 1 second on/1 second off, 5seconds on/5 seconds off), may help reduce subject habituation (in whichthe subject response to the stimulation decreases during stimulation).Additionally or alternatively, ramping the amplitude of the stimulationwaveform at the beginning of stimulation may increase comfort.

When the stimulator is configured to create a pulse-based electricalwaveform, the pulses may be any suitable pulses (e.g., a square pulse, ahaversine pulse, or the like). The pulses delivered by these waveformsmay by biphasic, alternating monophasic, or monophasic, or the like.When a pulse is biphasic, the pulse may include a pair of single phaseportions having opposite polarities (e.g., a first phase and acharge-balancing phase having an opposite polarity of the first phase).In some variations, it may be desirable to configure the biphasic pulseto be charge-balanced, so that the net charge delivered by the biphasicpulse is approximately zero. In some variations, a biphasic pulse may besymmetric, such that the first phase and the charge-balancing phase havethe same pulse width and amplitude. Having a symmetric biphasic pulsemay allow the same type of stimulus to be delivered to each nasalcavity. The pulses of a first phase may stimulate a first side of thenose (while providing a charge-balancing phase to a second side of thenose), while the pulses of the opposite phase may stimulate the secondside of the nose (while providing a charge-balancing phase to the firstside of the nose). In other variations, a biphasic pulse may beasymmetric, where the amplitude and/or pulse width of the first pulsemay differ from that of the charge-balancing phase. Additionally, eachphase of the biphasic pulse may be either voltage-controlled orcurrent-controlled. In some variations, both the first phase and thecharge-balancing phase of the biphasic pulse may be current-controlled.In other variations, both the first phase and the charge-balancing phaseof the biphasic pulse may be voltage-controlled. In still othervariations, the first phase of the biphasic pulse may becurrent-controlled, and the second phase of the biphasic pulse may bevoltage-controlled, or vice-versa.

In variations where the waveform comprises a biphasic pulse, thebiphasic pulse may have any suitable frequency, pulse widths, andamplitudes. For example, in instances where the stimulators describedhere are used to treat dry eye or otherwise produce a tearing responseby stimulating nasal or sinus tissue, the stimulator may be configuredto generate a biphasic pulse waveform at a frequency between about 0.1Hz and about 200 Hz. In some of these variations, the frequency ispreferably between about 10 Hz and about 60 Hz. In some of thesevariations, the frequency is preferably between about 25 Hz and about 35Hz. In others of these variations, the frequency is preferably betweenabout 50 Hz and about 90 Hz. In some of these variations, the frequencyis preferably between about 65 Hz and about 75 Hz. In other variations,the frequency is preferably between about 130 Hz and about 170 Hz. Insome of these variations, the frequency is preferably between about 145Hz and about 155 Hz. In some variations, high frequencies, such as thosebetween about 145 Hz and about 155 Hz may be too high for each pulse tostimulate/activate the target nerves. As a result, the stimulation maybe interpreted by the patient to have an element of randomness, which inturn may help to reduce subject habituation.

Similarly, for the treatment of dry eye, the when the stimulus iselectrical and the first phase of the biphasic pulse iscurrent-controlled, the first phase may preferably have an amplitudebetween about 10 μA and 100 mA. In some of these variations, theamplitude may be preferably between about 0.1 mA and about 10 mA. Whenthe first phase of the biphasic pulse is voltage-controlled, the firstphase may preferably have an amplitude between about 10 mV and about 100V. Additionally, the first phase may preferably have a pulse widthbetween about 1 μs and about 10 ms. In some of these variations, thepulse width may preferably be between about 10 μs and about 100 μs. Inother variations, the pulse width may preferably be between about 100 μsand about 1 ms.

When an electrical pulse waveform is an alternating monophasic pulsedwaveform, each pulse delivered by the stimulator may have a singlephase, and successive pulses may have alternating polarities. Generally,the alternating monophasic pulses are delivered in pairs at a givenfrequency (such as one or more of the frequencies listed above, such asbetween 30 Hz and 50 Hz), and may have an inter-pulse interval betweenthe first and second pulse of the pair (e.g., about 100 μs, between 50μs and 150 μs or the like). Each pulse may be current-controlled orvoltage-controlled, and consecutive pulses need not be bothcurrent-controlled or both voltage-controlled. In some variations wherethe pulse waveform is charged-balanced, the waveform may comprise apassive charge-balancing phase after delivery of a pair of monophasicpulses, which may allow the waveform to compensate for chargedifferences between the pulses.

When a stimulator configured to deliver an electrical stimulus ispositioned to place an electrode on either side of the nasal septum,alternating monophasic pulses may promote bilateral stimulation of nasaltissue. The pulses of a first phase may stimulate a first side of thenose (while providing a charge-balancing phase to a second side of thenose), while the pulses of the opposite phase may stimulate the secondside of the nose (while providing a charge-balancing phase to the firstside of the nose), since nerves may respond differently to anodic andcathodic pulses. The inter-pulse interval may give time for thestimulation provided by a first phase pulse to activate/polarize thetarget nerves prior to be reversed by an opposite phase pulse.

When a stimulator is configured to deliver a pulse-based waveform, thestimulation amplitude, pulse width, and frequency may be the same frompulse to pulse, or may vary over time. For example, in some variations,the amplitude of the pulses may vary over time. In some variations, theamplitude of pulses may vary according to a sinusoidal profile. In somevariations, the stimulation waveform may be a modulated high frequencysignal (e.g., sinusoidal), which may be modulated at a beat frequency ofthe ranges described above. In such variations, the carrier frequencymay be between about 100 Hz and about 100 kHz. In other variations, theamplitude of pulses may increase (linearly, exponentially, etc.) from aminimum value to a maximum value, drop to the minimum value, and repeatas necessary. In some variations, the user may be able to control thestimulus during its delivery. After the user has placed a portion of thenasal insertion prong(s) (e.g., the electrode or electrodes) in contactwith the nasal tissue, the user may increase the intensity of thestimulus. It may be desirable for the patient to increase the intensityof the stimulus until the stimulus causes paresthesia (e.g., tingling,tickling, prickling). As such, the patient may be able to self-determinethe proper stimulation intensity and self-adjust the stimulus to a leveleffective to achieve the desired result (e.g., tear production). It maybe desirable for the user to increase the intensity of the stimulusslowly in order to minimize discomfort.

In some instances, it may be desirable to configure the stimulationwaveform to minimize side effects. In some instances, it may bedesirable to promote stimulation of larger-diameter nerves (e.g.,afferent fibers of the trigeminal nerve), which may promote atherapeutic effect, while reducing the stimulation of smaller nerves(e.g., a-delta fibers, c fibers, sympathetic and parasympatheticfibers), which may result in pain, discomfort, or mucus production.Generally, for smaller pulse-widths, the activation threshold forlarger-diameter nerves may be lower than the activation threshold forthe smaller nerve fibers. Conversely, for larger pulse-widths, theactivation threshold for larger-diameter nerves may be higher than theactivation threshold for the smaller nerve fibers. Accordingly, in someinstances, it may be desirable to select a pulse width that preferablyactuations the larger-diameter nerves. In some variations, the pulsewidth may be between 30 μs and about 70 μs, or may be between about 30μs and about 150 μs.

It should be appreciated that the electrical stimulation devices andsystems described here may be used for one or more diagnostic functions,to modulate blood flow (e.g., to treat headaches), to promote healing,or the like. Additionally, the stimulation systems, devices, and methodsdescribed are herein are intended for use with human users, it should beappreciated that they may be modified for veterinary use.

Chemical Stimulus

In some variations, one or more chemical agents may be delivered tonasal or sinus tissue to treat one or more conditions. For example, insome variations, one or more chemical agents may be used to treat dryeye or otherwise promote a tear-producing response. In some of thesevariations, the chemical agent may be configured to promote trigeminalnerve activation. The chemical agent may be delivered in any suitablemanner. In some variations, the chemical agent may be delivered via astimulator as described herein. In other variations, the chemical agentmay be delivered via an inhaler, a nebulizer, or the like. In othervariations, the chemical agent may be delivered via one or more nasalsprays or eye drops (which may drain into the nasal or sinus cavitiesvia a nasolacrimal duct). The chemical agent may comprise one or more ofthe agents described above.

Mechanical, Thermal, Light-Base, and Magnetic Stimulus

As mentioned above, in some variations the stimulation systems describedhere may be used to provide mechanical, thermal, light-based and/ormagnetic stimulation. In some variations, a stimulator may be used todeliver vibrational energy to nasal or sinus tissue. In variations wherea stimulator comprises one or more prongs configured to be inserted atleast partially into a nasal cavity (such as the electrical stimulatorsdescribed herein), the prongs may be inserted at least partially into anasal cavity and made to vibrate. In variations where a stimulator isimplanted in a nasal or sinus cavity, one or more portions of thestimulator may vibrate while implanted. In some of these variations, thevibration may be generated using one or more magnets positionedexternally of the body.

Additionally or alternatively, ultrasonic energy may be delivered totissue by a stimulator comprising one or more ultrasound transducers. Invariations in which stimulators are configured to deliver one or morepulses of air to tissue, one or more pulses of air may be delivered tostimulate tissue. The pulses of air may be generated via a source ofcompressed air, or the like. In some variations, the gas may be warmedor cooled (e.g., mechanically or via one or more thermally-activatedfibers). In other variations, one or more portions of a stimulator maybe heated or cooled to provide thermal stimulation to tissue. Invariations where a stimulator comprises one or prongs configured to beinserted at least partially into a nasal cavity, the stimulator maycontrollably heat or cool the prongs. Additionally or alternatively, astimulator may use one or more light-generating or magneticfield-generating elements to stimulate nasal or sinus tissue.

Treatment Regimens

The stimulation methods described herein may be delivered according toone or more treatment regimens to treat a condition. For example, totreat dry eye, stimulation may be delivered to a subject as-neededand/or according to a pre-determined regimen. In some instances, a usermay use one of the stimulation devices described herein to provide around of stimulation when the user experiences symptoms of dry eye. Around of stimulation may have any suitable duration (e.g., between 1second and 10 minutes).

In other instances, the devices may be used to provide stimulation on ascheduled basis. For example, in some variations the stimulation devicesdescribed here may be used to provide a round of stimulation at leastonce daily, at least once weekly, or the like. In some variations, thestimulation devices may be used to deliver multiple rounds ofstimulation each day (e.g., at least two treatments daily, at leastthree treatments daily, at least four treatments daily, at least fivetreatments daily, at least six treatments daily, at least seventreatments daily, at least eight treatments daily, between two and tentimes daily, between four and eight times daily, or the like). In somevariations, the stimulation may be delivered at certain times of day. Inother variations, the stimulation may be delivered at any time duringthe day as desired or determined by the user. When the device is used toprovide stimulation on a scheduled basis, in some variations each roundof stimulation may be the same length (e.g., about 30 seconds, about 1minute, about 2 minutes, about 3 minutes, about 4 minutes, about 5minutes, about 10 minutes, or longer than 10 minutes). In othervariations, some rounds of stimulation may have different predeterminedlengths. In yet other variations, the user may choose the length of theround of stimulation. In some of these variations, the user may be givena minimum stimulation time (e.g., about 5 seconds, about 10 seconds,about 30 seconds, about 1 minute, about 2 minutes, about 3 minutes,about 5 minutes, or the like) and/or a maximum stimulation time (e.g.,about 1 minute, about 2 minutes, about 3 minutes, about 5 minutes, about10 minutes, about 20 minutes, or the like). In some instances, thedelivery schedule or stimulation parameters may be changed based on thetime of day (e.g., daytime use vs. nighttime use). In some of thesevariations, the stimulator may comprise (e.g., as part of a controlsubsystem) one or more counters and intelligence (e.g., amicrocontroller, programmable logic (e.g., a field-programmable gatearray), or application-specific integrated circuit (ASIC)). A countermay count oscillator pulses until a certain number have passed, at whichpoint stimulation may be activated. Additionally or alternatively, acounter may measure the duration of stimulation and the intelligence maycontrol the stimulation length.

In instances where the stimulation device is implantable, thestimulation may be delivered on a continuous basis. When an implantablestimulator is used to deliver stimulation non-continuously as discussedherein with respect to handheld stimulators, the implantable stimulatormay be configured to deliver stimulation automatically or may beconfigured to deliver stimulation on command. For example, in somevariations the stimulator may be configured to deliver stimulation on apre-programmed basis (e.g., according to a treatment regimen asdiscussed herein). In other variations, the stimulator may comprise oneor more sensors, and may be configured to deliver stimulation upondetecting a pre-determined condition with the one or more sensors. Forexample, in some variations, a stimulator may comprise a wetness sensor,and may be configured to deliver stimulation when the wetness sensorregisters a certain dry condition in a nasal or sinus cavity. When animplanted stimulator is activated by a user, an external controller maybe used (e.g., via a wireless signal such as Bluetooth, near-field RF,far-field RF, or the like) to activate the implanted stimulator.

Treatment Effects

In some variations, the treatment regimens described herein may be usedto treat dry eye. Current treatment options for dry eye are limited, andthey generally provide limited symptom relief or improvement in ocularhealth. In contrast to current treatment options, the treatment regimensusing the stimulators described herein may provide rapid and markedrelief and improvement in ocular health, as measured by numerousindicators, including tear production, patient symptoms, and corneal andconjunctival staining. Both the speed and magnitude of relief andimprovement in ocular health that may be achieved is surprising giventhe much slower and more limited ability to treat dry eye with existingtreatments. In some variations, the treatment regimens of providing thestimuli described herein may cause periodic or regular activation of thenasolacrimal reflex, which may in turn treat dry eye and/or improveocular health. Periodic or regular activation of the nasolacrimal reflexmay improve ocular health by several mechanisms of action. For example,the activation of the nasolacrimal reflex may cause tearing, which inturn may deliver growth factors contained in the tears to the ocularsurface. These growth factors include epidermal growth factor (EGF). EGFis a polypeptide that stimulates the growth of various tissues,including the cornea, conjunctiva, and goblet cells. In patients withdry eye, the cornea may become damaged due to desiccation andinflammation; EGF may thus play a role in stimulating the healingprocess for the cornea. Periodic or regular activation of thenasolacrimal reflex may also improve ocular health by increasing restingtear production, which may promote chronic hydration of the ocularsurface, as well as by causing periodic or regular significant increasesin tear production during activation. Activation of the nasolacrimalreflex may also improve ocular health by causing vasodilation, which mayin turn promote ocular health.

Example

A prospective, single phase, open label, single arm, non-randomizedstudy was carried out. Inclusion criteria included males and females 18year of age or older; a Schirmer's Tear Test (described below) withtopical anesthesia of less than or equal to 15 mm in 5 minutes in botheyes at least of two screening visits; at a first screening visit, aSchirmer's Tear Test with topical anesthesia and nasal stimulation witha cotton swab of at least twice or at least 10 mm higher than the firstof two unstimulated values in both eyes; a baseline Ocular SurfaceDisease Index (OSDI) score (described below) of at least 13 with no morethan 3 responses of “not applicable” at each of the two screeningvisits; normal lid anatomy, blinking function, and closure; andcorrected visual acuity of 20/200 (Snellen equivalent) or better in eacheye at both screening visits.

Subjects were provided a handheld stimulator probe as described hereinwith respect to FIG. 14, but without electrode covers 1418, and astimulator body producing a biphasic pulsed waveform with 300 μs perpulse at about 30 Hz and with amplitudes between about 0 mA and about 20mA. For the duration of the study, subjects were instructed to stoptaking their regular dry eye drops but were given over-the-counterartificial tears in unit dose vials to use if their dry eye symptomsbecame intolerable. Between office study visits, patients wereinstructed to perform nasal stimulation by placing the nasal insertionprongs of the stimulator probe in both nostrils, turning the device onusing the control knob of the stimulator body from the “off” positionuntil a “click” was felt, and then increasing the stimulation intensityby turning the control knob clockwise. Patients were instructed tostimulate at least four times a day (six times per day was encouraged),and more than four times a day as needed for relief of dry eye symptoms.As recorded in patient diaries, patients stimulated for about 30 secondsto about five minutes each time they stimulated, and between once pertoday and eight times per day.

At each study visit at day 0, day 7-10 (“Day 7”), day 14-17 (“Day 14”),day 26-34 (“Day 30”), days 53-67 (“Day 60”), days 76-104 (“Day 90”), anddays 150-210 (“Day 180”), tests to measure ocular health, including tearproduction, other objective measures of DED, and subject symptomrecording were performed prior to and after nasal stimulation in theclinic. These included dry eye symptom measurement, Ocular SurfaceDisease Index (OSDI), ocular surface staining, tear film breakup time,and Schirmer's Tear Test.

Dry eye symptoms were measured by the subject rating each ocular symptomdue to ocular dryness on a scale of 0% (no discomfort) to 100% (maximaldiscomfort), including the patient's general assessment of dry eyesymptom severity, dryness, sticky feeling, burning or stinging, foreignbody sensation, blurred vision, photophobia, and/or pain. The rating foreach was averaged to determine a symptom rating.

OSDI was measured by the subject answering 12 questions (I. Have youexperienced any of the following during the last week: Eyes that aresensitive to light? Eyes that feel gritty? Painful or sore eyes? Blurredvision? Poor vision? II. Have problems with your eyes limited you inperforming any of the following during the last week: Reading? Drivingat night? Working with a computer or bank machine (ATM)? Watching TV?III. Have your eyes felt uncomfortable in any of the followingsituations during the last week: Windy conditions? Places or areas withlow humidity (very dry)? Areas that are air conditioned?) by circlingthe number that best represented each answer: 4 (all of the time), 3(most of the time), 2 (half of the time), 1 (some of the time) or 0(none of the time). To obtain the total score for the questionnaire, thefinal score was calculated using the following formula: (A) Addsubtotals from Sections I, II, and III=A; (B) Determine total number ofquestions answered from Sections I, II, and III (do not include N/A)=B;(C) Final OSDI score=A×25 divided by B.

Improvement in ocular surface health was also measured by decreasedocular staining, including corneal and conjunctival staining. While inhealthy eyes the tear film may prevent the dye from adhering to theocular surface, the dye may adhere to the ocular surface of unhealthyeyes. Ocular surface staining was assessed and recorded by carrying outthe following steps in order: (1) Lissamine green conjunctival stainingwas performed using a Lissamine Green Ophthalmic Strip. The strip waswetted with sterile buffered saline and applied to the inferior bulbarconjunctiva. (2) After allowing lissamine green to remain on the eye for1 minute, the nasal and temporal conjunctival regions were graded on ascale of 0 to 5 using the Oxford pictorial grading scale. (3) Between1.0 to 5.0 micro-liters of non-preserved, 2% sodium fluorescein onstrips were instilled onto the bulbar conjunctiva without inducingreflex tearing. (4) The subject was instructed to blink naturallyseveral times without forced closure of the eyelid to distribute thefluorescein. (5) After allowing fluorescein to remain on the eye for atleast 1 minute, the 5 corneal regions were individually graded on ascale of 0 to 5 using the Oxford pictorial grading scale.

Tear film breakup time (TFBUT) was assessed using the following steps:(1) The slit-lamp was set to a magnification of approximately 10×. (2)With adequate fluorescein in place using strips, the subject was askedto stare straight ahead without blinking until told otherwise. Astopwatch was used to record the time between the last complete blinkand the first appearance of a growing micelle indicating tear-filmbreakup. (3) This procedure was repeated in the other eye.

Schirmer's Tear Test with topical anesthetic was used to assess tearproduction using the following steps: (1) Topical anesthetic drops of0.5% proparacaine hydrochloride (or other equivalent topical ocularanesthetic) were instilled in both the eyes of the subject. (2) Thesubject was instructed to keep the eyes closed for one minute. Afteropening the eyes, excess moisture in the inferior fornix was gentlyremoved with a cotton-tipped applicator. (3) After 5 minutes, Schirmerstrips (35 mm×5 mm size filter paper strip) were placed in each eye atthe junction of the middle and lateral thirds of the lower eye lid. (4)The test was performed under ambient light. The subject was instructedto look forward and to blink normally during the course of the test. Thetest was performed in a room with no direct blast of air on thesubject's face. (5) Strips were removed after 5 minutes from both eyesand the amount of wetting was recorded. (6) At the first screening visitonly, the Schirmer test was repeated a second time as described abovewith new Schirmer strips. (7) At the first screening visit only, theSchirmer test was repeated a third time as described above with newstrips adding cotton swab nasal stimulation. With the strips in place,the examiner inserted cotton swabs and gently probed both nasal middleturbinates of the nose simultaneously. After approximately 2 minutes,the probing could be repeated. The Schirmer strips remained in placeuntil after 5 minutes had elapsed. At the first screening visit, newanesthetic drops were added as necessary. Both basal and acutemeasurements were taken. Basal Schirmer's Tear Test measurements werebaseline tear production measurements, without acute stimulation (e.g.,without having stimulated at least within 30 minutes, at least within 2hours, or the like). Acute Schirmer's Tear Test measurements were takenduring stimulation with the patient's device as described above.

The average basal Schirmer scores for 24 patients are shown in FIG. 29Aand Table 1 below.

TABLE 1 Basal Schirmer Score Day (mm) 0 7.8 7 11.0 14 11.9 30 10.1 6011.4 90 12.1 180 13.2

As shown there, the patients' average basal Schirmer score increasedwithin one week of starting the treatment regimen, increasing by about3.2 mm during that time. Other treatment options may take significantlylonger to show improvement in basal Schirmer scores, and even then theimprovement in basal Schirmer score may be significantly less. After 90days of the treatment regimen described herein, the average basalSchirmer scores were about 4.3 mm higher than before beginningtreatment. In contrast, a treatment regimen of topical cyclosporine hasbeen measured to increase basal Schirmer scores by only about 0.3 mmafter ninety days of treatment (Sall, et. al. Two Multicenter,Randomized Studies of the Efficacy and Safety of Cyclosporine OphthalmicEmulsion in Moderate to Severe Dry Eye Disease. Ophthalmology, Vol107(4). 2000; FDA Restasis Statistical Review, CDER 21-023. 1999). Thus,the increase in average basal Schirmer scores over 90 days with thetreatment regimen described herein was more than 14 times the increasein average basal Schirmer scores with a treatment of cyclosporine. Atreatment regimen of a topical IL-1 agonist was not found tosubstantially change average Schirmer scores after 12 weeks (Amparo, etal. Topical Interleukin 1 Receptor Antagonist for Treatment of Dry EyeDisease. JAMA Ophthalmol, Vol 131(6). 2013).

The acute Schirmer scores for 24 patients are shown in FIG. 29B andTable 2 below.

TABLE 2 Acute Schirmer Score Day (mm) 0 21.6 7 21.0 14 19.8 30 20.1 6018.7 90 20.5 180 22.5

As shown there, the patients' average acute Schirmer scores were betweenabout 18 mm and about 23 mm. Thus, acute stimulation as described herewas able to cause average tearing significantly above the basal levels,increasing tearing from basal levels by between about 7 mm and about 14mm. FIG. 29C shows comparative data for basal and acute Schirmer scoresfor treatment regimens as described here with 19 patients, and basalSchirmer scores for standard treatment regimens of cyclosporine and anIL-1 agonist at 2.5% and 5%.

The average dry eye symptoms for 24 patients are shown in FIG. 30 andTable 3.

TABLE 3 DED Symptoms Value Day (%) 0 69 7 53 14 45 30 38 60 34 90 29 18028

As shown there, the patients' average dry eye symptoms decreased withinone week of starting the treatment regimen, decreasing by about 16percentage points on the scale during that time. The patients' averagedry eye symptoms continued to decrease by about 8 percentage points onthe scale in the following week, leading to a decrease of about 24percentage points on the scale within two weeks. The patients' averagedry eye symptoms decreased by about 31 percentage points on the scalewithin the first 30 days of starting the regimen, and decreased by about40 percentage points on the scale within 60 days of starting theregimen. As shown, this decrease in average dry eye symptoms wasmaintained over 180 days.

The average Ocular Surface Disease Index (OSDI) scores for 24 patientsare shown in FIG. 31A and Table 4.

TABLE 4 Day OSDI 0 64 7 46 14 37 30 30 60 31 90 26 180 28

As shown, the patients' average OSDI scores decreased within one week ofstarting the treatment regimen, decreasing by about 18 points (about28%) within that time. Other treatment options may take significantlylonger to relieve symptoms as measured by the OSDI, and even then theimprovement in OSDI scores may be significantly less. After two weeks ofa treatment regimen described herein, the patients' average OSDI scoreshad decreased by about 27 points (about 42%). After 30 days of atreatment regimen described herein, the patients' average OSDI scoreshad decreased by about 34 points (about 53%), and decreased by about 38points (about 59%) after 90 days. In contrast, as shown in FIG. 31B, atreatment regimen of cyclosporine has been measured to decreasepatients' average OSDI scores by about 15% after 90 days of treatment(Sall, et. al. Two Multicenter, Randomized Studies of the Efficacy andSafety of Cyclosporine Ophthalmic Emulsion in Moderate to Severe Dry EyeDisease. Ophthalmology, Vol 107(4). 2000; FDA Restasis StatisticalReview, CDER 21-023. 1999). A treatment regimen of a topical IL-1agonist has been measured to decrease patient's average OSDI scores byabout 30% and 35% after 12 weeks of treatment with 2.5% and 5% IL-1agonist, respectively (Amparo, et al. Topical Interleukin 1 ReceptorAntagonist for Treatment of Dry Eye Disease. AMA Ophthalmol, Vol 131(6).2013). FIG. 31B shows comparative normalized average OSDI scores for 19patients for treatment regimens as described here, and for treatmentregimens of topical cyclosporine and topical IL-1 at 2.5% and 5%.

Average corneal staining for 24 patients is shown in FIG. 32A and Table5, normalized to before starting the treatment regimen.

TABLE 5 Normalized Corneal Day Score 0 1 7 0.73 14 0.62 30 0.48 60 0.3990 0.38 180 0.31

As shown there, the patients' average corneal staining decreased withinone week of starting the treatment regimen, decreasing by about 27%during that time. Other treatment options may take significantly longerto show improved corneal staining. After two weeks of a treatmentregimen described here, the patients' average corneal staining decreasedby about 38%. The patients' average corneal staining decreased by about52% within the first 30 days of starting the regimen, decreased by about61% within 60 days of starting the regimen, and decreased by about 62%within 90 days of starting the regimen. In contrast, a treatment regimenof topical cyclosporine has been measured to decrease patients' averagecorneal staining by only about 23% after 90 days of treatment (Sall, et.al. Two Multicenter, Randomized Studies of the Efficacy and Safety ofCyclosporine Ophthalmic Emulsion in Moderate to Severe Dry Eye Disease.Ophthalmology, Vol 107(4). 2000; FDA Restasis Statistical Review, CDER21-023. 1999). A treatment regimen of topical IL-1 agonist has beenmeasured to decrease patient's average corneal staining by about 46% and17% after 12 weeks of treatment with 2.5% and 5% IL-1 agonist,respectively. FIG. 32B shows comparative normalized average cornealstaining for 19 patients with treatment regimens as described here, andfor treatment regimens of topical cyclosporine and topical IL-1 at 2.5%and 5% (Amparo, et al. Topical Interleukin 1 Receptor Antagonist forTreatment of Dry Eye Disease. JAMA Ophthalmol, Vol 131(6). 2013).

Average conjunctival staining for 24 patients is shown in FIG. 33A andTable 6, normalized to before starting the treatment regimen.

TABLE 6 Normalized Conjunctival Day Score 0 1 7 0.87 14 0.75 30 0.71 600.51 90 0.48 180 0.44

As shown there, the patients' average conjunctival staining decreasedwithin one week of starting the treatment regimen, decreasing by about13% within that time. Other treatment options may take significantlylonger to show improved conjunctival staining. The patients' averageconjunctival staining continued to decrease by about 12% in thefollowing week as compared to before starting the treatment regimen,leading to a decrease of about 25% within two weeks. The patients'average conjunctival staining decreased by about 29% within the first 30days of starting the regimen, decreased by about 49% within 60 days ofstarting the regimen, and decreased by about 52% within 90 days ofstarting the regimen. In contrast, a treatment regimen of topicalcyclosporine has been measured to decrease patients' averageconjunctival staining by only about 20% after 90 days of treatment. FIG.33B shows comparative normalized average conjunctival staining for 19patients for treatment regimens as described here, and for treatmentregimens of topical cyclosporine. Tear film breakup time was observed tostay relatively constant over the study period for the patientsobserved.

For the patients shown in FIGS. 29-34, the stimulus delivered was abiphasic pulsed waveform with 300 μs per pulse at about 30 Hz and withamplitudes between about 0 mA and about 20 mA, using the handheld deviceof FIG. 14 without covers 1418. However, it should be appreciated thatsimilar results may be found for other stimulus parameters (e.g., otherwaveforms as described above, other frequencies, other amplitudes, andthe like) and other stimulators, such as described herein.

1. A method of treating dry eye, comprising: delivering, in response todry eye symptoms, an electrical stimulus via an electrode to activate anerve in the anterior nasal cavity of the subject and thereby producetearing in the subject, wherein the electrode is disposed on astimulator and wherein the electrical stimulus is controlled by thesubject through a user interface of the stimulator.
 2. The method ofclaim 1, further comprising positioning the electrode and a secondelectrode in contact with nasal mucosa of the subject.
 3. The method ofclaim 2, wherein the electrode is positioned in a first nasal cavity ofthe subject and the second electrode is positioned in a second nasalcavity of the subject.
 4. The method of claim 1, wherein the electricalstimulus activates the nasolacrimal reflex.
 5. The method of claim 1,wherein the electrical stimulus comprises a biphasic symmetric pulsewaveform.
 6. The method of claim 1, wherein the electrical stimuluscomprises a waveform having a frequency between about 0.1 Hz and about150 Hz.
 7. The method of claim 1, wherein the electrical stimuluscomprises a waveform having a maximum amplitude between about 10 μA andabout 100 mA.
 8. The method of claim 1, wherein the electrical stimuluscomprises a waveform having varying peak-to-peak amplitude.
 9. Themethod of claim 1, wherein the electrical stimulus comprises a waveformhaving varying frequency.
 10. The method of claim 1, wherein theelectrode is positioned between about 20 mm and about 35 mm into a nasalcavity of the subject.
 11. The method of claim 1, further comprisingpositioning an electrode in contact with nasal mucosa of the subject anddelivering an electrical stimulus via the electrode to activate a nerveto thereby produce tearing in the subject on a second occasion.
 12. Themethod of claim 11, further comprising delivering an electrical stimulusvia an electrode at least once daily during a treatment periodcomprising a plurality of days.
 13. The method of claim 1, wherein anintensity of the electrical stimulus is controlled by the subjectthrough the user interface.
 14. The method of claim 13, wherein thestimulator provides feedback to the subject to indicate intensity of theelectrical stimulus.
 15. The method of claim 1, wherein a stimuluspattern of the electrical stimulus is controlled by the subject throughthe user interface.
 16. The method of claim 1, wherein duration of theelectrical stimulus is controlled by the subject through the userinterface.
 17. The method of claim 1, wherein start and stop of theelectrical stimulus is controlled by the subject through the userinterface.
 18. The method of claim 1, wherein the user interfacecomprises one or more buttons.
 19. The method of claim 1, wherein theelectrode comprises a hydrogel electrode.
 20. The method of claim 1,wherein the stimulator is held in a hand of the subject.